I think this and the next method could be simply called `truncate` and `thin`.  The `create` methods are really to contrast with the corresponding `apply` methods.  

In retrospect, now that I have a better handle on python mores, I think we should have made GSObjects immutable and had the `apply` methods act the way the `create` methods do currently.  But it would be a big overhaul to make that switch now.  But here, I don't think we need the verbosity of including `create` in the method name.