Los Angeles woodwind doubler Sal Lozano makes some basic points about flute-clarinet-saxophone doubling. This YouTube freebie appears to be a teaser for the video lessons you can purchase at Stars Teach Music, which has a surprisingly impressive roster of video woodwind teachers (mostly saxophonists).
I enjoyed this little clip by the esteemed Mr. Lozano, but I don’t think I would have paid the $4.97 for it at the commercial website.