This is a nice line with a testy and tenuous crux. Worth the walk up the hill.
Idiot Savant is on the right side of the tunnel. To get there, walk up the low-angle rock slabs that lead up and right. DO NOT walk up the dirt hillside- loose rock abounds that will just roll down and hit cars in the highway.
When you get a good ways up the slabs, you will begin to see some bolted lines. A big boulder splits the cliff in two - there are currently 4 bolted lines right of the boulder. Idiot Savant is to the right of the boulder, and can be easily recognized because it shares its anchor with another line (Indirect Savant, 12c)). Indirect is on the left; Idiot is on the right.
Although this route has always been referred to as .12a, it seems really, really soft for the grade. I have always considered it to be about .11b. In any case it is somewhat worth doing as a warm up for Twitch....