Most of the points have been put forward already, but presenting them together to the best of my ability for the strongest argument I can make:
Be it separate alignments (and thus, multiple awards) or a single award for any alignment, I think the idea has merit. Let's face it: as town, you are not in control of the game. You're one voice, among the many. Sometimes, things really are out of control. You can do literally everything in your power to try and win the game, to try and get people to follow you, and yet, sometimes, instead of it simply "not being good enough", it is
physically impossible
for you to have ever made a difference. We all know the type of scenario. (As just one hypothetical, imagine a town cop has a guilty on you and you're a VT. The result is only possible by trusting in the presence of, say, a framer. If you were any other player in the game, you'd be lynching yourself, but you
you're town. Yet there's absolutely nothing you can do.) When faced against people who will not budge, ever, no matter what argument you make, thus, sealing your fate. Especially when they have the backing of the scum. Because town refusing to listen to you and scum trying to make sure that continues can (and often does) lead to a situation in which winning their favor isn't just "well, they simply didn't have the skill to pull the right move". It's that there was no move that could have worked, and they were doomed to fail from the get-go.
The same is true for scum. Often, you will find scum that face insurmountable odds. Such as, say, one against 15. (Yes, it's happened.) With multiple town power roles still alive. If you think scum can win that situation, you're a liar. They face impossible odds, and yet, instead of giving up, they keep up the fight, and get close. But the inevitable catches up to them, as there is only so much you can do as one scum when there is a huge pile of town people (often many of them having evidence clearing them) still alive. One against ten. One against twelve. You get the idea. Many scum players have found themselves in that scenario...but instead of throwing in the towel, trying for the win. Some of them get close (the closest I've seen was Metal Sonic getting to 3P in Xeno), with 5p being a common "run out of time" for them. (There are a TON of examples of 1vMANY that end at that number.)
So in both cases (and both happen a fair amount), the player in question is devoting everything they possibly can to their alignment. They are trying, fighting, for the win harder than the call of duty obligates them to. As town, you could just give some reads, and give a defense, and if you get lynched, oh well. As scum, you can put in some nightkills, make some basic posting, and if you get lynched, oh well. A "best performance", though, is much, much more than that: the player goes above and beyond that call of duty, to try and truly win the game, putting in more effort than any other player does. It is them giving their best, in spite of facing odds that would tempt others to give up, even if they are ultimately unsuccessful.
Of course, this means the player nominated obviously is going to have skill, right?
Not necessarily. Sometimes, you have a player who has a single game where they shine, and that's it. (It's why Best Scumhunter and Cunning Manipulator are body of work awards, after all.) A "best performance" scummy can recognize that player, even though they didn't win. Furthermore, even if they
good enough, skilled enough, to be worthy of a scummy. As has been so said many times, realistically, who's going to win the scummy? The player who performed well in a game and won, or the player who performed well in a game yet lost? If their body of work is about equal, then the former will win 100% of the time, because of the mindset (conscious or not!) of, "Oh, the latter lost because they weren't as good as they could have been", when as discussed above, that is rather often not the case and their loss was out of their control. Naturally, in THEORY the player nominated for a loss could win. But in reality, they never, ever, EVER will, and again, if you think otherwise, you're being hopelessly naive.
It is basically a scummy that would be covering something that is worthy of acknowledgement, and yet not covered by other scummies. That's why I think the idea has merits. (Note that I'm presenting the strongest argument I can think of for the change; you'd be able to counter and dissect most of these points if you strongly disagreed enough to advocate against it.)
), and that means that they'd pretty much never get nom'd for a scummy due to the in-game play, but if there was a QT award of some kind...