My friend who got me into coaching, he said there was a period he went to China for training as a kid, and came out a wreck. For like six months, he had his worst results in a while. Then all of a sudden, he had his best results. Of course, these were in ancient times.I can relate. I do think that there’s a trade off as I focus on technique and building foundations at the expense of match play and winning. I’m hoping it will pay back over time!
I get the importance of formal competition and find it invaluable. But perspective is at least as important. Being very specific about what you do to win and lose points can help as well. There is little point developing an all powerful forehand if everyone knows that if they do a backhand serve into your forehand, you will pop it up for an easy kill. Your level may have changed, but it will hardly help in a situation where everyone knows the cheat code to playing you (other than making it inevitable that you have to address the weakness). IT's more fun to work on the killer forehand, but it is far more important to train serviceable return options for that short forehand serve, more so because the weakness will get easier to exploit as you get better.
I think the American weekly club league format, where you get bunched into groups with lots of opponents close to your level, is my favorite competition format for improving my TT. No easy matches unless you are a top of the top group and no one is close to you, you play lots of competition, and you have to stay sharp all through the event. And even if you are playing the same opponents every week, which can happen in some clubs, the variety tends to keep you sharp as people are often trying to figure you out just as you are trying to figure them out. Maintaining an advantage without real improvement is incredibly difficult.