Swampy, thanks for the good advice about getting used to the gearing when going faster. One of my practice TT courses has some descending on a false flat where I go 32-34mph (and other points north of 40mph) which is probably too quick for what you're recommending but I can see your point because I'm always flipping the right lever up and down looking for the right gear. Lanierb, I've made it a habit of always wearing my TT helmet on the TT bike, except when warming up or a TT. I don't like sweating the thing up then sitting there at the start house with a wet helmet.
Not that my opinion matters much compared to Hed and Cobb, but my testing has shown that head shrugged low with the tail flat is faster for me, I had always assumed Cobb's comment's about tail down vs tail up had to do with where the vents on the helmet were, if lowering the head and raising the tail takes the vents out of the airstream but since my helmet doesn't have vents in the front I figured down was better (again this has been backed up by my aero testing) but after reading that article I don't think my assumption was right. My current position is lower in the front than the picture in my profile and my head is lower as well and I'm pretty slippery.
Lanierb, Swampy wasn't talking about using video in a wind tunnel to give feedback on your positioning or actions, I think he means having a video of yourself in TT position on the road or a trainer and guessing what changes would improve power/CdA, you know the old "if it looks fast" adage. Because really how the wind moves is a bit of a mystery and without data I never assume a position is good or bad and while general rules are great they are based on averages and I for one am not average (in body proportions).
BTW, I started my TT bike L5 this week on a 2.2 mile course that used to be a local TT, the records for which are still on-line, and I was pretty quick. In fact I'd have been the 10th fastest finish there ever, on my first attempt.
I have a 40 km practice TT on the schedule this afternoon, so wish me luck.