You are more than advanced enough that I wouldn't be worried to deal with your blocks and you could be fixed by a good player if he was really concerned. My coach told me that he has never lost to a guy who couldn't flat block in the game warm ups because topspin blocks in warmups are evidence of bad technique and that at certain points, topspin becomes so heavy in matches that you can't arc it close to the table without counter-spinning - topspin blocking with an open angle will send the ball repeatedly high or long.
For uncoached players below USATT 1800 though, it is a different story. Many of those players have this illusion that in practice, if you loop hard, the opponent is supposed to start missing your loops by blocking them badly. This is not true. If you loop consistently, no matter how hard, as long as there is a consistent amount of spin on the ball, there is a flat block that brings your ball back on the table. Advanced players know this and calibrate their blocks and their loops for this in practice drills. Players without good coaching do all kinds of things like sidespinning or wiping the ball to keep their blocks on the table. These are better than topspin blocks in some cases but are still part of the problem. Rather than look for the flat block and getting good practice reps, they take pride in the fact that the practice partner is missing the block. This is a big mistake. In fact, 2500 players can miss bad blocks from 2000 level players in warmups if the block is not a good flat block.
The reason why these players tend to block long as the topspin increases is that lifting blocks with not so closed angles have a higher margin for error at lower levels of spin. As you get higher levels of power and spin, these lifting blocks will lift the ball long if the angle is not sufficiently closed (in other words, they have to start playing mini counter topspins, but since they almost never counter topspin below 1800 level if they are not coached, this is asking for a lot).
For someone like you who knows how to countertopspin, the challenge is getting to rely on a relatively flat contact and hit forward through the ball when blocking. It might run counter to how you are used to controlling the ball. Some very good players at your level or slightly higher have to go through drills to build out a flat block. I suspect in your case that the missing the table is what is bothering you about blocking. IF I coach people, I tell them that to calibrate their strokes, they have to deliberately miss the table or aim for spots and see if the ball goes where they aimed it with their technique. This is because many people do not really understand their strokes and the margin they have if they are aiming for the table all the time.
At higher levels, flat blocking is not always truly flat - the main thing though is to make sure that the motion of the ball and the stroke in the vertical plane isn't so large that it causes timing errors in both your stroke and those of the opponent. In matches though, some people are willing to take this risk in other to cause timing errors for opponents.
I will make sure that I will not stray away from the One True Path of flat blocking.
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There's one thing that I'd like to add on to.
the challenge is getting to rely on a relatively flat contact and hit forward through the ball when blocking.
Try holding the paddle with RPB. Now with your paddle 1 foot in front of your chest, try to open your racket. And then try to hit the ball flat. Have fun with that.
Anyone playing RPB knows that it is very difficult to open your racket, since the natural angle for doing RPB is very closed compared to shakehand. You have to apply pressure using your middle finger.
Because of this natural closed racket angle, my reaction block usually missed by going into the net. And so, I fixed that with my close-table lobbing method (which makes me lift the ball a little). This is exactly the 'missing the table' calibration that you were talking about.
It's quite coincidental that you mentioned the point about lifting without a closed racket, since I happen to be lifting a little with a closed racket due to RPB. Also, I don't have any trouble with really spinny loops. I just played in NCTTA regionals, where my block did completely fine against 2200 players loading their loops with spin (plus my practice partner loops spinny as well).
I will admit that initially I did not understand my own blocking stroke for a full 5 and a half years. But after a little thinking, I feel that now I have been enlightened (and the stroke finally clicked for me, hence the title of this thread)
EDIT: I've tried to control using only directional movement. It works out for my forehand. Not for my backhand. I do know how to control the ball this way ( in fact, this is how I loop and counter-loop now; no more peeling the ball; more solid contact ), but it doesn't work out when you close your paddle too far.
If anything, this is my next goal. If I can figure out how to control the ball with directional movement, I can finally start hitting harder with my backhand. As of right now, I am still 'peeling the ball' with my backhand attacks. When I do try directional control, it starts being inconsistent.
Perhaps with sufficient speed it is possible. But I still need to figure out a practical way to do this with RPB.
