Re: How long does it really take?
Well put Geoff.
Just a few days ago I found myself in a discussion about judo / jiu jitsu and Aikido and differences in approaches.
A friend of mine have taken judo many years back in a dojo where competition was not the main goal. Technique were practiced. In most other dojo's students were encouraged to start compeeting very soon. In his point of view this bore the risk of creating judo-ka's that rely on strength before technique.
I think the same thing can apply to Aikido. If you are primarily focused on learning Aikido as a selfdefence for 'realistic situations' (whatever that is) then I think you might miss the whole point of what Aikido can be. Aikido techniques can be used in at least two ways - but only by putting in the many many hours on the mat will you be able to perform the kind of magic that some of the really big stars are able to, and if you start out on with focus upon raw bodymechanics and physical power then I would expect the journey to effortless power would be quite a fair bit longer.
And of course the whole thing depends on the student, the teacher and about a million other factors.
I think I have heard more stories of people using their skill to avoid a 'combat situation' than to dishing out woop ass. This leads me to think that practicing Aikido as a quick route to fighting ability is probably not a clever strategy. Either train Aikido as it is and accept the different view upon conflict - or go do something else. Krav Maga, BJJ, wing chung or something along those lines would probably turn you into a fighter a lot faster than most styles of Aikido.