Which principles? "Train in the spirit of joy"? "Aikido is love"? Can a strengthened muscle not relax and work efficiently? How much muscular development is too much? Is it good that I can bench press 125lbs just because that is how strong by body is without training in lifting, but bad if I practice and can press 130 next week?
What, exactly, is kokyu, and why does nutrition affect it positively but strength training doesn't? What about having a 600 pound leg press (well, I used to....) is stopping me from using that same leg to step out of the way of a punch?
What is optimal, and why is it optimal, and is that optimization universal or a rather individual matter?
Well, it's a no brainer that conditioning that's good for one sport or type of sport is no good for another one - that's why marathon runners don't often look like powerlifters.
The problem with lifitng, if you're trying to do something Internal (let's assume that includes Aikido, for the sake of argument) is that it tends to condition the muscles to behave in the wrong ways for what you're trying to do. Not that it can't be done, if you're careful, but it's tricky enough that I wouldn't recommend it for anyone who's really interested in Internal work.
If you're interested in yank and crank - then it should work fine