I (and I guess, Dave) disagree with the two-people thing on an extended breaker bar.
I've been using 4'-6' lengths of pipe on a 1/2" or 3/4" drive bat handle for over 50 years (saying that always shocks me...) and the only time I needed two people as you describe was removing the lug nuts of truck wheels when we needed a 10"-12" long extension to get in to the nuts.
HOWEVER! I also have a 4' long piece of 2" wide by 1/4" thick flat steel stock with a couple of holes drilled to accept two wheel studs. That is assembled to the wheel and positioned so that when I loosen the nut (or tighten it later) I'm applying pressure towards that flat torque bar and the bar holds the wheel (or flywheel, hint, hint) in place without needing the brake applied or rocking the car dangerously.
When I do the rear wheel nuts on a Speedster, I either don't need an extension or, at most, a 2" jobbie, just to let the handle clear the fender. It's the extension that sets up weird torque vectors (remember your Physics 101 and torque vectors?) which force the extension off at an angle, thereby disengaging the socket.
BTW: I've had plenty of nuts rusted onto something so tight that my 300 ft/lb impact gun couldn't break them loose. Put a bat handle and 6' piece of pipe on them and gently increase the force and they back right out. And I NEVER "Bounce" the bar - that just gives abnormally high false torque. Never had a stud break off, either, if it's been soaked with penetrating oil for a while first.
Just figure out where, per your own weight, you should be standing on the bar a set distance from the socket pivot point for the proper torque and simply put one foot there, gently increasing pressure until all of your weight is on that one foot and when the bar stops moving, you're done.
Of course, having typed all this, if you're not comfortable with any of the use of this type of set up and want to stay safe with something you feel you can control better, then by all means, either buy a BIG torque wrench or get a torquemeister and "Git R Dun"!