keterys
First Post
I don't think so. The math speaks for itself, even against solos.
O-kay... let's examine that math then.

Flipping through my Monster Manual, from the beginning, looking for Solos.
In each case, I'm going to assume that you've exhausted any encounter/daily abilities you're going to use, and you're not able to hit more than one target with an area (and may possibly not want to use an area at all due to party positioning)
Tarrasque:
You're extremely likely to hit (Its Will is only +2 over its level), probably something like a 95% hit rate. Bit of an aberration for this, but it's the first one. It's late in the comat so it is frenzy-ing or trampling every round, so let's say it gets 3 attacks for, say, 25 average damage each. It's at level + 3 or level + 4 to hit vs. Reflex or AC respectively. Let's call it a 50% chance to hit, that's not that impressive but it gets to hit the non-defender a lot.
So, 75 damage * .5 = 37.5 per round average. -2 to hit drops that average to 30, a 20% drop in effective damage. That's certainly solid. So anyhow that's -19% damage from the -2 attack, which is slightly over 1/3 of the weaken effect. Definitely weak but still probably stronger than doing a couple more damage.
Beholder is next... let's see, its Will is actually respectable (better than the Tarrasque's, even 11 levels lower...) and it gets, say, 3 eye ray attacks from its aura, 2 central eye attacks from minors, and 2 eye ray attacks from a standard. Every 6 rounds it gets another 2 eye rays from frenzy, but I'll call that a wash with not doing some central eye rays. Its attacks are only +3, but vs a non-AC defense so we'll stick with the 50% hit rate for now. Some of these rays are not particularly threatening, but I'd say that restrain, unconscious, petrify, death, disintegrate, daze etc are all pretty serious effects. So, 40% of the time hitting and, say, half the time catching something you actually care about is really quite respectable in a group of 5 down to its at-wills. Better than almost any of the other options, and that's even on a high Will monster. Honestly, if just once it prevents someone from being slept before its turn (saving them from a disintegrate crit) or prevents a petrification or death save failure just once... it's really worthwhile. Of course, you could argue that the damage from Cloud of Daggers might have killed the beholder a round sooner, too (entirely possible).
Dracolich next (and last) - will is +12, so that's back to your 60% default. It has an okay bite, nasty breath weapon and the mesmerizing glare is just completely rude. So Bite is +5 vs AC, so still 50% and call it 20 damage (averaging in some stunned hits). The breath weapon is once every 3 rounds, is +3 vs Ref (so still 50%), does 16 and stun, 8 and no stun on miss, hitting say 3 people. Mesmerizing Glare will hit, say, 1 person in the blast 3 (at least once people realize) and is +2 vs. Will for stun. So 45% chance, I guess (it's odd how all the melee classes can have a reason to have a decent Will defense via stat upgrade, kinda nice change). Okay, 60% chance to reduce those to 40%, 40%, 35%... which results in about 4.8 damage less per bite, 8.6 less per breath and instead of... 2.85 people stunned per 3 turns, it'll be 2.49 people stunned. So ~6 less damage taken per round and, say, 3 less people being stunned over the course of the combat... which is worth more damage done and less damage taken.
Also factor in psychic lock, but that's a little complex since it's only one attack roll.
That said, one other thing that reducing hit gives you is that it lets you 'keep up' more easily, if you've got regeneration, temp hp generation, or status effect problems, neutralizing your enemy's action is very valuable for 'locking in' a win.
I'm not saying it's amazing, just that I think you were underrating it. I'm willing to concede I may have been overrating it though, given the above numbers.