I understand that others will prob'ly agree with you, projecting their worries onto my screen...all's I can do is tell you, it's not true.
You of all people should know that in true communication what you say isn't as important as what your listeners hear.
And if you do this, what exactly prevents their heels from flying up--not that they must, but that they might?
The fact they usually end up sitting on their can a few feet away. I have never once seen their feet come up anywhere near me.
Consider the following non-exhaustive Begging Hands alternatives (just the base and nothing but the base):
1) Do it as written. Two kicks, settle with double palm heels to the lower ribs. ("Do what you're told, its good for you." And it is good).
2) Do the kicks as chicken kicks, landing with the double palm heels as in #1. (Bruce Lee does Kenpo)
3) Do it as #1, but instead do downward outward torquing palm heels to the sternum area. From your palms up in the first move, do the kicks and then as you plant forward, thrust and rotate your hands inward to the sternum area -- when it hits it should look very similar to the "I have open hands" hand position in the salutation where the hands form a triangle. All in one move, continue the palm heels to spread away from eachother, as if you were pulling one side of the ribcage apart from the other (similar to the very first movement of Parting Wings). ("I wonder what would happen if I did something just a little different? Hmmm, not bad.")
4) One of my favorites -- eliminate the second kick from #3 above. Step back with palms pulled back, kick, plant forward with the palm heels to the clavicles (since they are bending forward at this point). Very fast, effective and powerful. Feels a lot like a wave. (Two front kicks in a row? Not for me.)
5) Another favorite -- do one right kick to the groin and plant with the lead palm heel to the head. Formulate and graft into your favorite right hand, right leg lead technique, or leave. This is a good alternative for big grabber v. small grabbee. (Some guys can take a pretty powerful strike to the midsection; its difficult to develop the muscle's around the groin and face to withstand impact.)
At any time you might catch me doing one of the above variations (or something else). They all work in their own little ways. That is the beauty of Kenpo. Take a base and see what you can get out of it.
But, heck, that is just one Idaho boy's way of looking at it -- what does he know?
Derek