The way I read that comment suggests that the attacker overextends his balance because he expects to hit the target. Is that what you mean?
Hmm - this is tougher to flesh out than appears to be the case.
Two well trained, evenly matched fighters, are not going to easily throw away their balance. However, in maintaining good balance it is very difficult to gain dominance. This is Aiki in the old sense.
At the right moment of attack a good fighter will sacrifice his balance in such away as to (assuming he got the timing right) overwhelm his opponent and still be able to recover that balance quickly.
Larry will know this situation from the Shodokan tsukuri driills.
I suppose that a good Aikidoist will be sensitive to that moment and take advantage of it but I also have to say, if all you have ever done is Aikido, than it is very easy to fool yourself that that attack/response to uke/tori reflects this situation. The training pattern becomes predictable and the value decreases because of this.