What I could never get my head around was the fact you could be flying merrily with a CPL doing say instructing work having never got your IR but as far as JAR were concerned (and I assume EASA) you've lost all your commercial theory credits if you then decide you want a FzATPL, however not if you just want a CPL/IR.
You already hold a valid CPL so why on earth do you need to do the CPL exams all over again in one case but not the other!?!?