I missed the conversation on roundhouse kicks... that's like my 2nd, er, 3rd, er, 4th favorite kind of kick. Eh, what the heck, I'll comment on it anyway.
As mentioned, flying kicks should never be used because of the vulnerability, and, more important, the lack of control. However, the basic principle - using mass and velocity to generate power instead of strength - is an important one. Learn it. Apply it. Question mark. Profit.
so I tend to like front kicks because I can take advantage of that for some pretty crazy height.
High kicks are usually disadvantageous. Feet/legs are farther from the intended target than hands/arms, therefore a kick is slower, therefore it is easier to defend against a kick. Kicks are also generally more tiring, and, frankly, if you need the extra power, you're doing it wrong. That being said and true enough, if you're throwing kicks, it may be best to aim high, as you don't want to actually hurt anyone and kicking the legs in a non-injuring way doesn't do much for your street cred.
To bring all of that together into one sentence: The day people learn to block a roundhouse kick to the ribs is the day I might have to break a knee >:P (Evil tongue out face?)
Also, I have bigger balls than all of you. So big they had to be strapped to my chest instead and declared boobs. ...
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Nah, I let the easy ones slide.
Point is: Entry's almost done. Should be in in, like, awhile.