Simon is someone Gasquet can actually push around, hence his dominant H2H.
He shouldn't though. Simon can actually flatten out his shots when he wants to, not to mention his rally FH is far superior to Gasquet's.
This is another reason Ferrer owns Gasquet: while not a weapon, Ferrer's rally FH is solid and he can get good depth on it, while Gasquet's sucks hence Ferrer dominates every FH exchange. That said, with Gasquet miles behind the baseline dropping plenty of short balls, even Ferrer's FH looks like a deadly weapon as he can easily dominate with it.