Yeah, he is.
I saw a skit the other day (Steve Whitmire was playing Ernie) where Bert convinced Ernie to think before playing his bugle or his drums and waking him up.
"If I play my bugle... it will wake Bert up. If I play my drums, that'll wake Bert up too! I know! I'll play my bugle and my drums! But wait. Think. That'll wake up Bert too! Oh, wow! I did it! I thought before I did anything! I've got to tell Bert! Hey, Bert! Wake up, Bert! I've got something important to tell you, Bert!"
"Ernie, what is it?"
"Bert! I thought before I played my bugle and my drums! If I had played them, I would have woken you up! Oh, but now that your awake, I can play my bugle and my drums again! Yaaaaay!"