Get to grips with the marquee tool's endless possibilities, and you could soon be a Logic power user.
Your personal choice for the Command-click tool is one of those things that separates Logic operators. It reflects how we think and move as 'power' users. It can be argued that the Marquee is the most important tool for editing and navigation, and is, therefore, the best choice for Command-click. But even if you have already selected Marquee for this esteemed status, you might not yet have discovered all of the possibilities this opens up.
Point & Snip
If you work in Logic at all, you will know the Pointer tool — the primary tool for selecting — and will probably have explored the Tool Menus in the upper right of the Arrange window to assign your default mouse tool and Command-click.
You can always temporarily grab a tool from the left side of the Tool Menus (the Esc key opens the same), but if you want to work fast in Logic, assign a tool to the right-hand column of the Tool Menus and get into the habit of quickly switching to it with the Command key.
For Pro Tools users, the Marquee tool is closely related to the Selector tool. With the Pointer as the main tool in Logic and the Marquee as the alternate tool, you are most closely replicating the Pro Tools Smart Tool (which combines the Hand, Trim and Selector Tools).
For cutting, the Scissors might be the more intuitive tool to the new Logic user, and for years it was the only choice. But consider this: with the Marquee tool, you can drag across a region or multiple regions to select an area. Then you can quickly perform all critical cutting and other editing functions, such as muting or deleting parts of a region or multiple regions, or extend the start and end point of your Marquee selection with the Shift key. It's super-easy to apply Marquee swipe edits in real time while the transport is running, which is especially handy if there are other musicians in the room: there's no need to interrupt the groove by stopping the music to perform an edit.
By using Marquee selection across tracks, you can quickly make edits to multiple regions at a time.
Of course, simple editing operations can be carried out perfectly well with the Scissors tool, but if you get in the habit of using the Marquee tool instead for selecting regions to cut and mute, you'll have the power Logic habit down of grabbing Marquee as your Swiss Army knife for a long list of other navigation and edit functions. With a little practice, at least a few of these will become 'go to' moves when you're in the flow of production with Logic.
If you get used to the many different ways to use the Marquee tool, it will quickly become an essential tool for many more tasks than you might expect.
Marquee Edits
Let's take a look at the Marquee edit functions available to you in Logic, and how they work:
Marquee Cut: Marquee-select across an area of a region, or of multiple regions, then click into the Marquee-selected area with the Pointer tool by releasing the Command key (if Marquee is your Command-click tool). The areas are snipped on either side, creating independent regions. Alternatively, you can double-click with the Marquee to cut the region into two.
With Marquee Cut, there's rarely any reason to use the older Scissors tool for basic cutting. (My only exception is the can't-live-without Option-Scissors for making equal slices within a region on the beat.) The Scissors tool requires two separate incisions on either side of an area in order to isolate a new region.
Marquee Mute: Marquee-select across an area of a region or of multiple regions, then hit the 'M' key to mute the selection. Both sides of the highlighted area are cut, creating an independent region or regions.
Marquee-Option-Copy: Marquee-select across an area of a region, or of multiple regions, then Option-drag with the Pointer tool to copy the highlighted area to another place in the timeline. The cuts in the original Marquee selection are automatically 'healed' and will no longer be visible.
Marquee-Selection Paste: The Marquee selection can be an insertion point for pasting content from the clipboard. When you click and hold with the Marquee tool, a help tag appears indicating the bar and beat position of your location, so you can make an exact selection in time to place the region or note events.
Marquee-Select Empty Space: When you cut, copy or paste a Marquee selection, the empty space in the selection is included. This is perfect for editing regions that don't start on the downbeat of a bar or beat. After making the selection, you must use Command+C to copy, then Command+V to paste at the new location and select that destination with your Marquee tool. Unfortunately, Option-drag doesn't work here for copying the selected area, and it's easy to forget to select the destination with your Marquee tool.
Set Locators by Marquee: Set a cycle area by your Marquee selection simply by clicking on the Set Locators tool in the toolbar after making the selection. This Set Locators tool works for regions too. Once selected, you can easily repeat, insert and cut within the locators.
Set locators with your Marquee tool, and you can easily make edits within the selection.
Secret Treasures
These ones are a little more hidden, so you might not have come across them before:
Single-Pixel Marquee: Click into the Arrange workspace with the Marquee tool, which will create a thin white vertical line. When you hit the spacebar to enable playback, the playhead will jump to this 'single pixel' marquee insertion point. Even if there is a cycle area selected in the bar ruler, the single pixel playback start point will take priority. To remove the single pixel mark, click anywhere in the workspace with the Pointer tool. 
Using the Marquee tool to make a single-pixel selection sets a point between bars that takes priority over playback, even if it is within a cycle area.
This is an especially friendly move to Pro Tools users adverse to the traditional Logic playback technique of moving the mouse all the way up to the lower half of the bar ruler to set a playback start point. But even for Logic users, the ability to leave the cycle area intact and quickly play from a location outside the cycle is handy.
Marquee-Select Automation: This move alone may sell you on the Marquee tool. Hit 'A' to enable Automation view, Marquee-select any area of automation, then click back in with the Pointer tool. Four nodes are created, letting you easily draw in volume rides.
If you go to the Automation view and then Marquee-select an area, when you click back into the area with the Pointer tool, four nodes will have been created so that you can adjust the level of that section.
Single-Pixel Marquee and Delete Key to Cut: Click into a region with the Marquee tool to create a thin white vertical line. Hit the Delete key and a cut will be made in the region.
Marquee Swipe & Marquee Stripe: Swipe across multiple tracks with the Marquee tool to create a region selection across tracks. After making a Marquee tool selection, select mute with the key command 'M' or click in with the Delete tool to remove: instant breakdowns for one beat, two beats or a whole bar, for example.
Here's an interesting option: activate the Marquee Stripe area in the bar ruler by clicking on the music note in the upper right of the Arrange window just below the Tool Menus. With Marquee Stripe enabled, drag across the upper area of the bar ruler to define a Marquee selection across tracks and perform multitrack edits.
Transients
Marquee Snap to Transients ('Tab to Transient'): Tab to Transient is the Pro Tools term for using the Tab key to jump forward and backwards between transients. Logic implemented a similar feature with the Marquee tool. Click into the audio file with the Marquee tool after zooming all the way in, then use your left and right arrow keys to jump to the previous and next transient respectively.
If there is a Marquee selection, the right and left arrows adjust the end of the selection, snapping to transients. Shift-left/right arrows behave similarly for the left selection border.
Marquee Cut on Transient: A quick editing technique is to hit the delete key after selecting a transient with your Marquee tool to cut on that transient. Continue with forward/rewind by transient after the cut. Also, Shift-select between transients with the Marquee tool so the area between is shaded. Then, use the Delete key to quickly cut on both sides and create a region.
Quick Swipe Marquee Record: If you want to record over a section of audio, Marquee-select the area to punch in, then hit Record. The Autopunch light will come on in the transport and a thin cycle area appears in the bar ruler. Logic drops into Record mode but records only over the Marquee selection. This achieves the same results as enabling Autopunch in the transport and making the bar ruler selection.
Forward/Rewind by Transient with Marquee: Click into an audio region with the Marquee tool and cursor left or right to move the marquee insertion to the next or previous transient, then cut with the Delete key, for example.
Escape Route
It's good to know that the Logic tools you grab with your mouse can be as dynamic as your creative ideas. The Tool menus are incredibly useful, but the Esc key is also handy, when your mouse is far from the upper-right side of the screen: it pops the toolbox open right where your mouse is and your eye is focused. One way or another, get into a rhythm of fast tool switching and you'll be an Olympic Logic user.
