Long Pips Sponge

I am now quite confused.

My trainer says "less sponge=more control"

You are saying that "more sponge=more control"

And these are just examples

Additionally,the head of the table tennis association,who is a powerful player and also has quite good knowledge about equipment,says the same thing as you,but the equipment specialist,the best table tennis equipment seller in my district agrees with my trainer.
So what is the true?

You four are all very experienced players and all have much better equipment knowledge than me.
But everyone of you is saying different things.
So it confuses me.

Hi, DK

I know this post is a little old but I thought I'd add my thoughts anyway.

Alois and your head of TTA are right: the less sponge you have with pimples (especially OX, no sponge) the more erratic some shots will be precisely because of the "pimple effect", depending on just how the ball comes into contact with the pimples.  This erratic effect is good if it confuses your opponent, but obviously not so good if it causes what feels like a mis-hit.

With a sponge, especially a thicker sponge, your shots will be more predictable and, in that sense, more controllable because the ball can sink into the sponge and pimples.  Where you might say that a thicker sponge is less controllable is when the ball tends to boomerang off your bat and, say, go long off the end of the table (eg, when chopping hard from too close to the table).