Page 292 of the DMG clearly states that spells are not subject to damage reduction. Complete psionic therefore either unintentionally broke the already established rules (demonstrating its poor editing) or created an even more unfair disparity between magic and psionics (demonstrating its poor game design).
Of course magic should just go through everything, right? right?
Like it or not, that's the status quo. Psionics are being kneecapped out of a falsely perceived balance issue. And in some ways, yes, this is due to the fact that WotC has a hard time forcing themselves to occasionally hand everyone else nice things.
The two problems that psionics have is that early editions weren't build that well, and it's named "psionics."
That last one is really rankling. Nevermind that Vancian is a magic system cribbed directly from a sci-fi series, and involves complex formula and experimentation in order to cast things like "telepathy." Clearly psionics, the magic sstem where you use your will and mind to force reality to alter, is the science fiction one!
As for balance, psions fall under all of the wrongful imbalance cries that I've seen. I'll give the three biggest reasons and, to make it a bit fun, I'll be comparing them to a much weaker class who's called overpowered for many of the same reasons, one that will make you "wat" rather hard: the warlock.
Yes. People believe the warlock is overpowered.
1) It's different, so it must be too powerful!
I've seen someone claim that psionics fans are all horrible munchkins. Why? "If you want to play a different ruleset, there has to be some trick in it that I haven't seen." People, especially those more set in their ways, are
terrified of things being different. Believe it or not, there are people who to this day believe warlocks are too powerful, simply because they don't use Vancian. It's why wizards and clerics in some places are seen as, wish I were joking,
weak - because they're
traditional. I've seen people ban the goddamn Truenamer because they were afraid it might be too powerful.
It's also why people refer to increased books as being an incresed chance for munchkins, and why they'll ban all non-core books in an attempt to help
non-casters. It doesn't matter that Core was scewed right from the start - it's familiar, so clearly it can't be at fault! No, it's those other, new, different books, they're the ones to blame!
2) It's easier to use, so it must be too powerful!
This is the sorcerer vs wizard argument. Most people here will readily agree - wizards are better then sorcerers. But there are indeed people who will disagree. Why? Because it's easier to accidentally be an awesome sorcerer then it is a wizard. Sorcerers are "easier" to use - choose your spells and start mashing them at baddies. The pros of a wizard look like cons to new players. Where we see "I can change m spells every day!" they see "I have to change them
every day?!" To very crudely show it:
Wizard - New player power: 4. Experienced player power: 10
Sorcerer - New player power: 6. Experienced player power: 8
These numbers are made up on the spot. Please don't try to look deeply into them.
I think psions hit the same place sorcerers do. Power points are easier to understand then vancian. They're also more familiar - pretty much every video game ever uses them, DDO. A lot of psion fans like myself call the system elegant - it's easy to jump into, and takes a bit of use to fully begin to master it. But because it's easy to jump into, it's easy to make
Likewise, the warlock isn't exactly a difficult class to understand. Hey look a baddie. I shoot it with my magic beam. Wait now it's a magic fire beam. This is also incidentally why people keep playing blaster wizards only to whine about psions doing more damage then the wizard.
They have no goddamn clue what they're doing. Blaster wizards hey that looks easy I'll just fireball everything and - look at that, I'm not really contributing that much. But it sure was
easy to understand!
3) Oh god what are these rule things
or! I am so bad at math.
They just didn't care. Maybe the DM never bothered reading through the rules. Maybe the whole party has no clue how the CR system works. Maybe the DM is forgetting the assumption of multiple fights in one day. Regardless, this leads to some hilarious viewpoints regarding balance. Take the fights per day problem. This is what leads to the whinging over novas, especially regarding psions. The opposite is what caused people to initially think the goddamn
warlock would be
too powerful. "It can cast ALL DAY LONG? Preposterous!" Of course, when you're assumed to have an average of x battles, casting all day long really doesn't matter that much. Likewise, if you blow all your load right from the start, your DM will be just as upset as your girlfriend, and you'll find yourself unable to continue playing with either for the rest of the day.
The rule bit needs no real look into. Glance at any person countering on why psionics isn't overpowered, and at least half their points will be "No, read the goddamn rules, jesus, it doesn't work like that."
Most of these fall under "Eh, whatever." They just don't care. This is the worst of the three, because you can't fight it. They don't care what your responses are, it's still overpowered "because." They don't care that their view of the rules is factually incorrect. They don't care that nova-ing is a rather stupid idea, or that being able to cast all day isn't that impressive. And you can't convince them otherwise, because
they don't care.