Look. People are allowed to like Harimoto, to not care about his screaming, to hate Harimoto, to hate his screaming, and anything in between. Both sides of this debate are silly.
For Fais, from my standpoint, I am not sure there is a tactic that works aside from something Der said: "If you keep winning points, the guy who is screaming will have far fewer opportunities to scream."
For those who don't like watching a match with a kid who screams at cheap points caused by mishits, so what. What will your complaining about it do? Turn off the volume or just don't watch.
For those of you trying to criticize the people who don't like Harimoto because of his screaming, your rational is lame and your motivation is just as annoying, trying to make the people who don't like it look bad and trying to insist they must be lower level players, that stuff just makes you seem petty: who carez what level.
When you play someone who yells, you find out if it bothers you or not. If it does, it is part of the game. If it doesn't, that head game doesn't work on you. I have seen both from players whose level was quite high.
I have also seen antics way way way way worse than Harimoto's screams. Stuff that is vile. Some of the players with a stong mental game figure out how to use it to their advantage. But not all players are in that category regardless of how high a level they are.
I just don't see this, as things are framed in this thread, to be a topic worth discussing. A strategy that works for one player against someone using yelling and mind games may not work for another player. And that second player's strategy may not work for the first.
Fais, if yelling as your opponent yells works when you play a screamer, great. I know that would not work for me and I wonder if it would work for anyone. Test it out and tell us if it worked for you. I would be interested in hearing those results. Discussing strategies different people use when facing someone who is effective at playing mind games would be a useful discussion. But criticizing someone for liking Harimoto, or criticizing someone for not liking his screaming, well, that is just circular and goes nowhere. Both sides have a right to their feelings about Harimoto, but once they are criticizing someone for feeling different, then there is a problem.
For me, someone else yelling usually does not bother me. If I was on the next court, and it was happening in the middle of points, it would. But not if I was playing the person. I have seen other mind games that work way better than a little bit of shrieking. And as far as I can see, Harimoto uses the shrieking to pump himself up; not as a mind game. Some people need to be more pumped up than others. I play best when I am calm. But I also know someone who plays his best when he is frothing mad and wants to cause physical harm to his opponent. So, everyone has their own optimum level of stress that brings out their best.
But, if your opponent yelling on points won, regardless of how they were won, gets inside your head, then, figuring out something that works for you seems to make sense to me. But don't think that what works for you will work for others.
For me, by the time I am set to serve or receive, I don't really have anything in my head except focusing on the ball and what the opponent does with the ball in real time. To me it seems that stuff that happened between points can't effect you if you are focusing on the things you should during the points.
So, despite the intention of the OP which was completely different than the bulk of the comments after, I honestly feel the discussion up to now is pointless:
-- "I hate Harimoto because he screams."
-- "Stop whining, you must suck."
So far I have not seen that either side of this has anything useful to offer. Sorry. But both of you should stop. In my opinion, neither side of that argument looks good.