You complete contradict yourself. He IS worried about smoothness...not weight transition in this case but the smoothness of engaging the dogs. Also this Jean chap seems pretty handy behind the wheel, so perhaps he is capable of deciding that he wants to upset the car with the handbrake (acting on the rear wheels) but would like to heel toe to stop the front wheels decelerating even more.
I'm going to try and summarise the info. in this thread so it's actually useful...
BENEFITS
Mechanical Sympathy
- It avoids using the clutch as another braking surface which will obviously wear it prematurely.
- Avoids unnecessary stress and strain on gear box internals as the speeds of input and output are matched before re-engaging the clutch rather than being forced to match.
- It allows you to rev match for non-syncro (dog) boxes which as you've stated helps engage the gears and reduces wear. This is equally applicable to a syncro box as you're not working the syncros so hard. It easier for them to match a difference of 100rpm rather than 2500rpm.
Balance & Smoothness
- Prevents extra weight transfer unsettling the balance of the car when re-engaging the clutch. Important when braking hard into a corner. If you're on track you'll often be braking on the threshold of grip/slip and a non-matched shift might be enough to lock the wheels.
- Also of benefit to passengers, a seamless shift is much more comfortable as your head isn't thrown forward as if someone just pressed the brakes even harder. One of the main reasons to use it on road as well as track!
- Prevents locking the rear wheels in a rear wheel drive car.
Skill
- It's fun to learn new skills and put them into practice. Be that heel & toe, left foot braking or taking an advanced driving course.
THE TECHNIQUE
Pivot w/heel:
http://www.youtube.com/watch?v=IuoZeuSgEj4
Pivot w/side:
http://www.youtube.com/watch?v=qdWSyrqEnE4
The videos above show the two main techniques. You can pivot on the ball of your foot and use the side of your heel or you can 'roll' the side of your foot across. Although the name suggests toe I would avoid trying to use your big toe for braking. The most important part of the maneuver is the braking. Safety first and all that. So I would use the ball of your foot under your big toe.
The Clio is one of the best cars to heel and toe in that I have driven. If you're having trouble doing it then it's likely to be down to inexperience rather than the type of shoes or the size of your feet.
Some cars will not allow you to heel and toe and they cut the throttle when you brake...modern VW's for example. Useless.
I would say that when driving the thinner the shoe the better, skate shoes have thick soles and give you no feel what so ever. If you heel toe properly you don't need the extra width of a special pedal or a big pair of shoes.
Would it be a good idea to create some threads that have factual information on advanced road and race craft driving techniques so people can fully understand the benefits of these techniques? If that is the case we can gather together all the info, filter out the rubbish and create an FAQ that is factual and informative?
An understanding of what goes on inside and engine and gear box will be of great help to full understanding the technique.