During 20 years of driving, I've had blowouts at high speed on race tracks and highways, with passenger cars and trucks. Not once did I lose control of the vehicle.
Granted, there was an element of luck involved; but mostly it was knowing what to do in the emergency. All the professional drivers I know agree that the average motorist has a good chance of surviving tire failure at turnpike speed, without hurting himself or his car, if he knows what to do.
You've got two things in your favor right off the bat - the new 55 mph speed limit and modern tires. Tire reliability gets better all the time. In fact, you may never have a tire failure, but it can happen. If it does, here are some guidelines.
When a blowout occurs, take your foot off the gas pedal immediately. Don't jam on the brakes, unless you're in immediate danger of rear-ending someone. If you lock up the brakes (wheels stop rotating), you lose all control of the car - and that's true flat tire or otherwise. If you make a quick stop, brakes should be applied firmly, but with a sensitive foot. For quickest stops, brakes should be applied so the wheels are almost locked but are still turning.
Once the car stops, or gets down to a manageable speed (5 to 10 mph), turn on your blinkers and get to an area where you can safely change to your spare tire.
The safest procedure, if a rest area or service station isn't handy, is to pull off to the side of the road on a level spot. Avoid a curve or just after a curve.
It's a good idea to carry reflectors or flares for such emergencies. If you have hazard lights, leave them on. If not, turn on your signal on the side closest to the road. If the turn signal is on your trunk lid, leave the trunk lid shut. If you have a passenger, he or she can step a few hundred feet behind the car to warn oncoming motorists.
Turn the engine is off, put the transmission is in part (first gear or reverse if it's manual), and the parking brake on. Front wheels should point straight ahead.
Remove the jack, spare tire and lug wrench from the trunk; don't wait until the car is jacked up since you're more likely to knock the car off the jack.
Pry off the hub cap, then jack the car up until some weight is off the wheel, but with the wheel still firmly on the ground. Take the lug wrench and break the lug nuts loose. Just turn them enough - maybe a quarterturn - so they'll wind out easily when the wheel is all the way off the ground.
Then jack the car up until the wheel is off the ground, remove the lug nuts and pull the wheel off the hub. Never put feet or arms under the car while removing the wheel.
Place the spare tire on the wheel hub and replace the lug nuts. Smug the lug nuts up semi-tight with your lug wrench, let the car down enough so the wheel is touching the ground, then finish the tightening.