Cool thread y'alls got going here.
Said rider could also be really good at this technique.
Link to original page on YouTube.
The read of much of this thread sounds real close to the skills of A riders at Mid-Ohio. Much, much different track layout, but nearly the same sequence of events.
The entry line to Mid-O's carousel looks very similar to the above graphic, the hook turn technique can be to tighten the line mid corner to tighten the line for the very late apex of the carousel. Then you are faced with a very quick chicane that dumps you on the front straight. We short shift squarely in the middle of the chicane to stay in the throttle and get the bike online for a tight apex onto the straight. There is about 8ft of elevation change (downhill) to sweeten the deal. 
Have a go at the video and compare to what you are seeing to gain additional knowledge. Sometimes riders leave out the little things or just take them for granted if you know what I mean... and it just takes knowing what to look for.
Bonus: DannoXYZ mentioned that the rider reduces lean angle just a bit at the exit of the turn. So many riders are notoriously lazy at the exit of a turn, perhaps there is another rider skill at play here? Hint: yes there is.