heel toe shifting is used more for downshifting to keep engine speed and transmission speed at par, so it is mostly used for negotiating turns at highspeeds, see simply downshifting can cause the back end of the car to come out as all the weight is thrown onto the front of the car making there little traction in the rear, as well simply downshifting is hard on the transmission, the proper technique would be downshifting, and using the brake to slow the vehicle and the gas to keep the revs at par with the transmission, this is done by applying the break with your toe and controlling the gas with you heel and of course the clutch with your left foot, there are some great videos on youtube demonstrating this! haha hopefully my confusing explanation didnt confuse you more! | 
Question about Shifting 
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