With Tab to Transients enabled, the Tab key moves the Location Cursor to transients and clip boundaries within a clip group.
With Tab to Transients disabled, the Tab key moves the Location Cursor to clip group boundaries only (and the sync point, if present).
Trimming clip groups with the Standard Trim tool works the same way as trimming regular clips, regardless of whether you are trimming a single-track clip group or a multitrack clip group.
Trimming a clip group does not trim the underlying clips, but rather trims the clip group boundaries. All underlying clips retain their original length and location. This is true for all underlying audio and MIDI clips, and nested clip groups. If you trim the clip group shorter, underlying clips may not be heard on playback because they are outside the clip boundaries of the trimmed clip group.
When trimming clip groups with the TC/E Trim tool, it applies only to audio
or MIDI clips, depending on which clip type in the group you trim, and creates a new clip over the clip group.
If you ungroup clips after trimming a clip group in (shorter), audio clips falling outside of the bounds of the current clip group are trimmed to fit the clip group boundary or removed.