"Jack, you have debauched my sloth!"
Oh crap! I forgot that Contrary would turn the Bulldoze Speed drop into a boost. Whoops!If Serperior is indeed Contrary, then you just gave them a speed boost on turn 2, and get KO'd on 4 before the sub can go up (barring a miss). No help there.
Gliscor also has access to Steel Wing, which doesn't do as much damage as Bulldoze and is less likely to be useful coverage. But it does have even more PP, can mise the occasional defense boost to make some matchups easier (as opposed to Metal Claw, which has more PP still but puts the miser's boost in a less useful stat), and its typing may convince the opponent to make a resist switch to a Water-type, possibly giving up a matchup they might have been able to brute-force through eventually for one where Slowbro can often come in for nearly free and laugh all the way to the bank. If you decide to go the route of "I don't particularly care how much use Gliscor gets out of the damage formula, period", that's also an option.