Re: why focus on internal power
In reading this thread, I think different people are defining what they mean by "internal power" in whatever way they see fit. Probably, if everyone understood what "internal power" was, there wouldn't be this mishmash of statements equating "strong personal strength" and various other things as "internal power".
I agree (and have said numerous times) that someone who can use ki/kokyu power is not necessarily doing Aikido. Aikido takes practice and knowledge. On the other hand, I don't see how anyone who does not have ki-power can be said to do Aikido or even "aiki". The idea that the ki skills are some side-issue to Aikido, like whether you wear a hakama or not, really highlights what a problem there is in Aikido today. And in other arts, as well, I should add.