I've been using this exploit for a while now. It's the only way to make Shouting actually viable as a form of combat rather than a special attack move you get to use once every few battles. Summoning a thunderstorm when assaulting a bandit fort, followed by using whirlwind sprint to get behind an archer and then using unrelenting force to throw them off the ledge is great fun.
The thing is, it is not supposed to be a viable form of combat on its own. It is supposed to be a "special attack move" that you use in a dire situation, or to cripple your enemy in the beginning of the fight. Shouts takes a support role in Skyrim. The only thing i could see implemented is that shouts would be divided into three groups, with separate recharge timers. Group 1 are damaging shouts (unrelenting force, ice form, fire breath), Group 2 are supporting shouts (become eternal, kynes peace, whirlwind sprint) and group 3 are "mega shouts" (call dragon, stormcall).