That can only be true when you define aikido broad enough so that only the goal matters, not the means to achieve the goal. Or put differently, so that only the destination matters, not the road you took to get there. The problem with such a broad definition is that you'll have to include certain activities that are most definitely not aikido, precisely because of that broadness.
Anyhow, if it isn't your training methodology that defines your aikido, then what does?
Actually I'd say the definition is narrower. Those that broaden the definition call things Aikido when to me they aren't.
Including the training itself.
Loosely ...Training is the activities undertaken to learn to change the body and mind and in time to co-ordinate the two
You can stick two beginners together in a class and ask them to follow the teachers instruction.
Are either of them doing what I think of as Aikido?
I say no.
If being in an 'Aikido' class was all it took then press ups sit ups or any other activity used to warm up could be classified as 'Aikido'.
Again I do not think this is the case.
"Aikido" is performed by only the most skilled with the rest working toward this goal through a training methodology.
The training methodology is just the training methodology - It is very important of course but sadly all to often becomes the goal itself.