What a load of crap.
Clutching is the right way to do it. And you are on the right track. The idea is to get it pretty high with just the clutch, and adjust from there with the throttle. Now its really tempting to shut off the throttle as soon as it comes up, couse it scares you.
So here is what you should do. Start practicing at low speed, bring it up with the clutch just high enough not to make you nervous. a foot or two, something that you know isnt going to flip you over. At low speed (25mph) you shouldnt need much throttle to do it. Bring it up, and try to ride it out. Dont close the throttle, your going slow, and bringing it up low, so you're not going to flip. Once you can ride a low wheelie for a little ways (no need to chase it to 100mph, once you hit 50-60 go ahead and drop it) try controlling the height with the throttle. Give it abit more gas and bring it up some more, or maybe get off the gas, and get back on it to sort of move it up and down in the air. The idea is to get comfortable with it, couse thats whats slowing you down, just being afraid of it.
Once you get to the point that you dont close the throttle after you clutch, start working on height. Add abit at a time, not pushing your comfort level too far. As you lift it higher, you will ride the wheelie longer before you get to the 60mph "Go ahead and drop it" mark.
Powering a wheelie is good to get started but you wont get those nice 12 oclocks with power. No one does, there are too many variables. With the clutch method you can set the height of your original "Jump" by how fast you feather the clutch, and the rest is easy buisness
wear your gear. Cover the rear brake.