Every once in a while we get a complained from a player saying their new rubber sheet developed a crack! This can happen to any brand when speed glue is used incorrectly.
What happens when to much glue is applied?

The glue not only penetrates the sponge, it also goes into the top sheet making it very soft, much softer than it should be!

Some players will not apply the glue evenly which is very important to do.
We noticed that some players apply more glue in the middle in which case the glue will penetrate the sponge and the top sheet making it super soft.

Players start ripping forehands right after rubber has been applied to the blade, this is the main cause for a top sheet to crack or bubble and table tennis manufacturers will not guaranty damage caused by improper gluing.

Over the years we have seen damage like this with all kinds of rubber brands ever since players started using speed glue in 1980's.
I have seen it at the 89 and 91 Worlds when the world ranked players used speed glue and players with heavy topspin would crack their rubber and complain about it!

Mr. G