It's just that ducking into knees from bobbing/weaving isn't as big a deal as people like to think. Why? Because most Boxers know how to defend or get out of the way of uppercuts, and uppercuts are just as likely to catch a guy from underneath as a knee.
Kabuki - you have any videos or can describe bobbing/weaving while defending from uppercuts?
I'm just wondering if you can clarify the mechanics since my sparring partners who do the crazy low weaving, man I would have to crouch down to uppercut them! Their head while weaving is beneath uppercut solar plexus level