I think there are more efficient ways than SICP to learn Lisp if you're already a competent programmer. Scheme was my first functional language and I picked it up directly from R5RS. Then I moved over to CL by skimming ANSI Common Lisp and then reading On Lisp.
I would agree with that if you wanted to pick up the syntax.
The initial chapters of either R5RS and Ansi CL don't make it obvious how scheme/lisp are different from Algol, except the (()).
It's worth pointing out that you won't get far without doing the exercises in the book too. In fact, I recommend working through the book and only watching a video lecture if you're unclear on the material.
