I know it's illegal to have both rubber sides of the table tennis blade be the same color. Is it illegal to have one side with the smooth part of the rubber, and another with the pimpled (anti-spin) rubber?
I'm refering to ITTF standards.
The ITTF Handbook's racket section doesn't forbid it.
This method for assembling a racket is advantageous for those looking to both be able to spin with smooth rubber that has a good spin factor, and counter spin with an anti-spin rubber in the same game (as oppose to trying to counter a spin with another spin).