Arranger Track Part Heights

Can anyone tell me why the part heights change when moving them? Example in this video:

https://vimeo.com/114374796

Yeah behaviour of the arranger part height is infuriating!

I think its because the previous part has a long name and even though its truncated on screen there’s a ‘bug’ which makes the next parts along think they need to shrink to make room for the long name which isn’t there because its been truncated…

Adjust the name length of the previous part - does this effect it?

Mike.