Well, 2 might be an exaggeration - but not far off. The 17th level NPC fighter (generally the worst of the will savers) from the DMG needs an 11; give him +5 cloak of resistance (improved on +3), luckstone, a wisdom item (and often better stats, either trhough better starting rolls or wishes, or both) and it looks a lot better.
Ad remember, this is the guy who will be weakest - and again, there's a lot of defences available that will stop that attack dead. The Vrock needs surprise to make it work.
Is this the broken version of
mass heal they are casting!?

Actually, the version I've been using heals 100 points.
Well it gives them +4, not much I agree though.
Yes, the problem is their save stats are usually very low, and their HD are also very low compared to other creatures encountered at their CR.
If you don't agree with some (or all?) of the CR factors then which of them do you believe overly inflates the Pit Fiends CR?
I wish I could answer that. Also, the problem I have is less with the top demons/devils, but more with the inermediate ones (like the Vrock, Glabrezu, etc).
I haven't worked out how they are costed, it's just that the final number seems to high - the most obvious thing to think of, for me, is the fact that they have many spell abilities, only a few of which they will get any real mileage out of, and even if all were equally useful, they only have a couple of rounds to use them (or longer, using the hit-and-run tactics for which they are suited - but even that doesn't necessarily take them far).
Those foolish Intelligence 20/Wisdom 20 geniuses you mean.
Yeah, well, they have to operate within the confines of the GMs INT & WIS
I would be interested in hearing a recount of how the Pit Fiends were subsequently beaten.
I struggle to remember the exact order of events, but use of Time Stop (using the variant rule: no targetted spells), the Fighter's Devastating Critical ("Kill the Pit fiend!" Splat! "What Pit fiend? Dammit - No-one else within reach so I lose the rest of my attacks"

. Dimensional anchor stopped one from teleporting, so the monk (!) wasted it. The sorcerer had used spectral hand to cohort using spectral hand to drop see invisibility on people, and the other sorcerer has see invisibility cast as a persistent spell.
One of the pit fiends did flee (after terrifying the cleric), once the other two were toast.
We'll see. It should be interesting if nothing else.
Agreed.
Darren