Re: do a technique or flow into one?
@Alberto, to continue with the boxing analogy, the flaw I see in your argument is that the basic unit of boxing is not really a punch, it's a combination. And you certainly do see people practice specific combinations, and practice set combinations against set defenses.
A punch in boxing is more like a single movement inside a larger technique, like the tenkan inside of kote-gaishi. And single punches are practiced as drills, just as single movements in Aikido are practiced as drills. Sure, no one spends a whole session practicing nothing but hooks, but that's a silly argument--no one spends a whole session practicing only tenkan, either.
Really, look at beginners on the mat--most of them can't even do the prescribed throw or take the prescribed ukemi without leaving themselves open a dozen different ways. What hope do they have if they start making stuff up?
As someone I respect says, if you practice chaos, you learn chaos.