Re: Aikido vs Brazilian Jujutsu
Agree with Don, as usual.
Iriminage is a form of takedown. to do a takedown you have to pretty much clinch, or enter behind. So you need to be versatile in many ways to off balance and put him on the ground.
Obviously in reality, there are strikes and all that too.
It is correct, that you certainly would not "shoot for a double" or go for an ankle if you were standing. Although if you were on the ground, I could see where you might want to do this depending on the situation.
Bottomline, you should be well rounded. Why limit yourself to NOT training takedowns of many flavors. Better to have and not need, than to need and not have.
Of course there are high probability techniques that you should practice more.