Posted this in the old thread, but I'm reposting this here so it doesn't get missed.
Disarm was one of the most annoying, fun destroying parts of pvp, before the masteries were introduced. There was nothing worse than getting into a disarm duel on a dexxer. It wasn't just that it was frustrating and annoying, it meant that a fight could go on indefinitely with no way for the character depending on melee skills to get the kill shot. I used to call it "the disarm circle jerk". The character with disarm gets low in health, disarms the dexxer, and the dexxer runs around in circles, or off screens, until the character can rearm—rinse, repeat.
The weapons masteries fixed that, and it was the only good reason to take up a weapon mastery. Without the saving throw vs. disarm, the weapon masteries are worthless, because the weapons mastery specials are useless. Anything those special moves do, you can do faster and cheaper, in terms of mana cost, with a weapon special.
And I've said this before, but if you want to get a little "RP" and look for a smidgen of suspension of disbelief, there is no way a legendary weapons master, that is strong and dexterous, should be able to be disarmed, ever, period. It's the kind of thing that happens to an untrained child picking up a weapon for the first time, not a seasoned warrior.
And you could still be disarmed even with the mastery, it just didn't happen *ALL*. *THE*. *TIME*., which is what used to happen before the weapon masteries were added, and what will happen again if the saving throw vs. disarm is taken away.