Tom Cashel said:
First of all, any DM worth his salt can keep these spells balanced. No need to air out your personal shortcomings and insecurities here, my friend.
Just to note, I'm not getting involved in the flame war here, I've always respected Tom's opinions in the Harm debates.
However, I've heard this argument many times before concerning many different threads, and personally consider it bunk.
While many people on these forums are great dms, many dms across the world that play the game are simply average. The system should not require a dm's skills to keep the game balanced.
For instance, in the polymorph other/shapechange/shifter arguments, many have said "well if you just don't use certain monsters, then the players will never get those forms and it will be balanced." And I say if a Dm's creativity is ever limited by the players then something is horribly wrong.
Its the same with harm. In order to protect my monsters from harm, I have to think up a host of quirky magic items, special monsters, and advanced tactics to keep harm in its place. Every time I create a good monster, I then have to go "oh wait, what about harm. Damn, guess I'll have to change this guy." And many Dms can do that, many even enjoy doing that. But however, many can't or don't want to, and they shouldn't be expected to just to maintain the balance of a few spells.
I have seen other good arguments for keeping harm the way it is, many from Tom himself, but I don't agree wtih this one.