Need shorter visemes when inserting manually

Many times the automatic lip sync function does a great job at making the mouth move with the audio track.

Sometimes the automatic process is horrible, and has to be corrected manually.

Very often the following happens:

1. I need two or three visemes in a 7-frame space in the timeline.

2. I right-click and add the first viseme in the sequence, and it fills the entire space where I actually need three visemes.

3. There is no way to disconnect the newly added viseme from the following one and shorten it to the proper length, so I can insert the next two visemes. The inserted viseme glues itself to the following viseme.

Please reduce the length of inserted visemes to two frames, and let the user decide how long it needs to be.

(Or create a way to separate two visemes that are glued together.)