I find Booster Energy and Bulk Up to be anti-synergistic. There could be a tug-of-war going on where you switch that Bulk Up Pokemon in a few times during the match. It's just a hunch, but I feel like those sets would probably fare far better with Leftovers or with extra coverage. Leftovers looks better on Great Tusk, while extra coverage (or First Impression) would make Booster Energy Slither Wing feel far better to use.