Kamikaze Midget said:
This is why the fighter needs the cleric. And why the wizard should be tossing fireballs and lightning bolts at the creature from a distance. And why the party needs to stay generally away from it unless it can only get off one attack.
The Girallon is a fine CR5 monster, as it will drain a party's resources -- but not wipe them out. With a rogue, a wizard, a cleric, and a fighter, the guy's nothing more than a tough physical customer. Charm him, hold him, slow him, ranged attack him -- he can't touch you and he's meat in a matter of rounds.
Not every monster problem should be solved by going up next to it and hitting it on the head until it dies. Sure, a CR5 Fey may be the perfect victim of that, but a big four-armed gorilla? You expect it to hit like a pansy little elf?! 
While I agree with your use of tactical logic here, part of my problem with CRs has and always been the assumptions made about standard magic level, group size, and class makeup. I feel this logic has caused a great many members of our community to fall back into straight-jacketing a number of people into roles. By the way I'm not sure this exists on EN World from the postings i have seen, just a blanket generalization, that will probably end upshooting me in the foot in later.. I'm not quite sure how you could fix this, but the more general challenge codes and experience system evidenced in Wheel of time goes a long ways IMNSHO.
I guess that I'd like to advocate, a more general awareness of the assumptions involved in the CR system, you'd be surprised by the amount of people that don't read beyond surface details. I sound harsh, I don't mean to sound harsh, but while some rules are solid the impact they bring about in the world at large is not solid. If this is a jumbled mess, it's because I'm a jumbled mess of a person.
Edit: After reading Mike Mearls post on useful critiquing, I thought I'd offer an apology for his post. I am actually quite greatful for the CR system and how much easier it has made locating monster candidates to fit a challenge. My point here is simply this, the emphasis of it as a guideline as well as most of the other 3e rules as guidelines was in my opinion a little underemphasized, and this has effected me in my endeavors as a DM. I'll try to be a little more balanced in my approach to subjects from now on. I will not however edit out my previous comments, because I view them as valid opinions, expressed wrongly through the passion of the moment. As raw emotions I believe they also serve to further my point, even if they do sound a tad disrespectful.
