I'm not sure about CL lectures in general. In regards to applying CL to SICP, I would argue that the course is more about the underlying concepts than the lang

I'm not sure about CL lectures in general. In regards to applying CL to SICP, I would argue that the course is more about the underlying concepts than the language itself. You could probably read a CL reference and write your exercise code in CL instead of Scheme, or just learn CL after the course and it wouldn't be a big leap.