Yeah, it's pretty easy to get past many obstacles by simply cheesing the physics engine. That's why I like the co-op, for the dumb fun harassing your partner with floating boxes and the like. The Trine games are pretty nice looking, and the characters and plot are funny, so overall I found it pretty enjoyable. Also, my co-op partner and I enjoyed the challenge of finding all the experience points and secrets.
It's no Lara Croft: Guardian of Light, but it's fun.