have any information on a boy changing a primary handle (not the alias) and still retaining full review credits?

One is an LA hobbyists who changed his handle because it had his name in it (same with one down here with his name and zip in it). Some people realize they can be potentially identified and contact TER who will change their handle but still have the reviews and email connected to it.  

...someone else thought that it needed to be changed.

I started out under a different primary handle in 2002, but after my ex-GF at the time gave me serious grief about it when I didn't clear my history after using her computer once (talk about lesson learned), I decided to keep my activity private.

It's standard procedure. If you change your handle all your reviews and your old board posts get assigned to the new handle.