I also love Steam but It's just a bit too similar to the mighty Sledgehammer. As for Kiss That Frog I don't think it's meant to be taken that seriously.
I agree about the similarities between Sledgehammer and Steam. And for that matter I lump Kiss That Frog into the same category of those two songs—uptempo with a heavy wink toward sexual innuendos. My take is that PG was trying to recapture the musical—and commercial—magic of Sledgehammer.