>>44958270There is huge amount of difference in the amount of pressure an Excadrill in Sand can exert immediately compared to a Mold Breaker set that needs to waste a turn to get a +1 speed boost.
Just consider all the stuff a Sandrush Excadrill can revenge kill that a Mold Breaker one won't.
Having a +2 boost immediately after being sent out also means it can run adamant or even run Choice Band instead of being forced to run Jolly non-Choiced like Mold Breaker is.
There's also the benefits Sand in general brings to the table, like cancelling opposing weathers, the Rock type SpDef boost which can make stuff like Rhyperior unkillable, and the huge amounts of chipping defensive pokemon will be taking over time, many of which no longer even run leftovers to cancel it.
