This is an unbelievable game plan. 12 pitches, 12 sliders. It’s not like he’s a one trick pony, the fastball also grades as an excellent pitch with obviously elite velo.
To be fair his regular season load is not that egregious for a reliever. Jeff Hoffman for instance pitched 6 more innings and got into 7 more games. Not sure if keeping his usage low in the regular season was on purpose but he should be pretty fresh all things considered.