Wasn't there an artical about similar practices in Helicopter magazine a year or so ago?. I can't say if it was the same company, they never published the companies name, but if I recall correctly Transport took a look at one guys log book and decided that his solo -(with an instructor riding along but not acting as an instructor) didnt really count as solo time and he had to do it all over again.
I havn't seen the COPA artical in question, don't know what it says about the practice, but it seems to me if a school trains you to go solo, but doesnt trust you enough in it's machine to let you go out on your own, then maybe its time to question your teachers....
tDawe