Funny post - everyone has their own style, and all of them are right given the situation:
Normal driving with someone respectable in the car (or a hot pizza, or cup of coffee between your legs): Leave in highest "practical" gear, brake almost to stop then put clutch in and idle at the light/stopsign in neutral. No downshifting except as necessary to keep the engine in a reasonable rev range/powerband for the task at hand. This is smoothest and least jarring for passengers, and for situations when you want your driving to be a background activity, only noticed by its smoothness and absence of "Sturm und Drang". This is actually most likely to get you a "hey, he's a good driver" compliment from your passengers.
Faster driving (alone in car, not too aggressive): See above, maybe heel-and-toe rev-match downshift (no double-clutch) for corners just because it sounds nice and puts the engine nicely in the powerband for your apex-and-later acceleration. Be nice to others, don't cut folks off, etc. This is fun.
Aggressive driving: Heel-and-toe rev-match downshift for corners and when slowing, but when you know you're stopping (like for a light), save the trans/clutch/synchros the wear and just use the brakes as they were intended (unless you're really addicted to the sound).
Downshifting when youre coming to a complete stop might make folks think you have a sequential trans, and sounds like Colin MacRae coming into a rally hairpin, but is pretty much completely unnecessary in a synchro trans like the MSP.
Double-Clutching (described above) does limit synchro wear as it "spins up" the trans innards under no load to match the revs. This may be a minor difference on the synchros but when they do go it's expensive to replace. It doesn't appreciably wear the clutch any more than a heel-and-toe rev-match non double-clutch downshift - the only difference is the clutch spinning a few gears and a shaft inside the trans.
Downshifting does cause more wear on the drivetrain but if you're smooth, rev-match,and don't slip the clutch it's not *too* bad. There are some transmissions/clutches ('80's BMW's I believe) that don't take well to transmitting torque the other way (deceleration), and so the habit may be damaging to other cars in your stable (if you HAVE a stable...)
"Heel and Toe": The "heel" referred to is the right side (pinky-toe-side) of your right foot - think "heel of your hand". Don't know the origin of the phrase (maybe Brits?) but it does NOT mean turning your foot 90 degrees to use your other "heel". "Heel and Toeing" means using the pinky-toe side of your foot to blip the throttle while braking with the big-toe-side of your foot so you match revs with the lower gear while braking. Downshifting without rev-matching (either via heel-and-toe, or just a throttle blip) does wear the clutch - as much as a hard start would, only some clutches don't tolerate reverse torque as well as others.
As a rule: Brakes are for deceleration, Engines for acceleration. Downshifting is mainly to keep the engine in the powerband for acceleration. Exceptions exist:
- No-brake-light deceleration - but be careful - while this is sometimes "necessary", it can be obnoxious and Johnny Law can seriously bring some blame to you if you're rear-ended, because a safety device - brake lights - is not working or properly used. Yeah, they shouldn't be following so closely, but it's happened and the charge sticks because there's something in your control that you can do to avoid an accident but you choose not to do it. Think of a witness in another car saying "his brake lights never came on".
- Brake failure: Had this happen - good to know you can stop the car without them. A rare occurrance, however
Hope this helps - remember, different techniques for different purposes and different circumstances. Different costs for different techniques. It has plusses and minuses - you decide what's best for your circumstance.
OK, enough.
it's kinda awkward at first, but you get used to it
