Updates:
Status: Fixed
Comment #8 on issue 799 by chisvasi...(a)gmail.com: Editing code in Glamour
must be faster
http://code.google.com/p/moose-technology/issues/detail?id=799
The problem was that PluggableTextMorph was created with autoAccept: true.
This means that GLMMorphicModel>>accept:notifying: is called on each key
stroke which completely replaces the text, recompiles it and redoes the
highlighting twice.