Double clutching? These are modern vehicles people with syncros, your not driving a mack truck...

A short blip of the throttle while dropping down a gear is all you should need for a smooth down shift.

Also, never ever down shift in a turn, with any car. This is a good way to get in trouble. I could go into the physics, but Im going to be lazy and just say "dont do it."

 

I shift in turns all the time, depends on what I'm doing. If im trying to go faster through a turn i'll keep it in a lower gear to keep the power up and shift on the exit. But usually I'm just lazy and dont drive too hard lol Not like i'm speed racer or something lol 5 G's ON THE SKID PAD!!!

 

If you had any track experience, you would not be shifting in the turn... Trust me.

Grabbing a gear upon exit is fine, its just the change in inertia when depressing the clutch and revving the engine that can cause a car to go out of control mid turn if you shift mid corner thats the issue. Done perfectly, it shouldnt effect much. But if you can go around a corner maintaining your line and execute a perfect downshift with no change in the velocity of the vehicle, you should be paid for your services. (in other words its damn near impossible)

No driving instructor in the country would condone mid corner gear changes. If you have to change gears mid corner, you went in the corner with the wrong gear...

 

TO add to the heal toe thing I remember when I drove one of the race cars out in calgary I notices that all the pedals were at the same level (height) whatever you want to call it.

I notice on our cars, the clutch is quite far out, breaks is sort of in the middle, and the gas is quite a bit closer to the firewall which could be causing issues with your ability to heal/toe properly.

 

The brake and throttle placement in our Lancers is far from ideal for Heal-Toe. New pedals can help with heal-toe use, but a brake pedal relocation kit would go a long way to make heal-toe much easier to do and much easier to modulate the engine RPMs while shifting this way.

 

I heel-toe downshifting all the time. specially comming off the highway.