Audio Stretch problem

Sometimes when I  split a section out of a large clip in order to stretch it, the whole thing bounces forward without stretching.
 
This may be because the split section actually contains all the original audio and doesn't know how to respond to the stretching.
 
To fix this I "bounce to clips" first, then stretch it and "bounce to clips" again.
"Bouncing to clips" crops the invisible audio away making the clip smaller.
 
Any other ideas on this?
Steve