No, not really, there are several similar equations and they all place the saddle very similar. It gives a starting point, some modern cleated cycling shoes require the saddle to be a tad higher because of the stack up. It is also needed to take into account crank diameter and foot size/length which is why I said it is a starting point. But, it will get you very close. I would be wary of deviating significantly from the computed height.

It is important to get as good PBH measurement. You will need a helper, also a hard cover book with about a 1 inch spine. Press it up into the crotch with similar force exerted by your saddle. Be sure you are in stocking feet, naturally spread, back against the wall, standing straight. Push that book up there TIGHT!!!!!! Make the mark on the wall (your helper presses the book and makes the mark).

I know it is fashionable in some circles now to jack the saddle way high so that the hips rock or the legs have to reach. You should be able to drop your heels slightly at the bottom of the pedal stroke with the knee not quite straight, if you cannot do that, you are too high.

In fact, .67 X PBH is considered the best power position for long distance road racing and is somewhat universal in use by cycling coaches and many riders.