Cliff has some serious doubts about Jake's technical knowhow, to the point of thinking he can't even read a leveler. When doing construction, the smallest thing can result in very big problems, so no harm in double checking, just to be sure. As it turns out, Jake does know what he's talking about, and is pretty handy with the right tool. Besides, Jake points out that "straight and level" aren't the only way to go, and he goes to work on Cliff's tool which is more than up for the job.