While I do not know in detail for Mezz I know for Ibanez (japanese guitars and basses) how they do their "velvet touch".
It's all about the proper filler (less) and top coating and then removing just about the right amount of it again with the proper grit (not too fine!).
The top coating is not glossy (which gets sticky) but more matte.
That way the wood is protected but you still get a smooth, woody, cool/fresh (not sticky or hot) feeling of the wood.
Cheers,
M