So how do you ever really train the real Qi/Ki if you do some hard, some soft? Don't you wind up with some (sure it can be strong, but that's not the Full Banana) muscle-based jin?
I don't really know enough about qi/ki or jin for them to be useful concepts for my training. I've found it more fruitful (for me personally) to focus on elements like alignment, breath, proprioceptive and kinesthetic awareness. I think I'm getting a little understanding of "intent" as it is talked about here on Aikiweb, but even that is not something I'm sure about in practice. So when I have the opportunity to work with someone like you or Ark or Dan, I'm really interested in the hands-on work, watching and feeling what you guys do, watching and feeling what partners do, trying to get a non-verbal kinesthetic grok on that, and keeping any discussion or questions to plain English.
So I don't know what real qi or full-banana jin is. I think I understand you to be alluding to a danger of hard/tension work building a reliance or habit of muscling and rigid frame. That may be true, and something I'll have to be on the lookout for. I guess I think about Ark's discussion about building the budo body, and seeing how he teaches and demonstrates the Aunkai exercises for beginners. There is a lot of tension work initially, and later (again, in my limited understanding), partly with improving physical condition and partly with increased internal awareness, the student can "back off" from an emphasis on tension. I can't put it any more specifically than that, given my limited experience with Aunkai.
The "soft" or cotton-end of the tension range is, in my personal experience and training, more useful with identifying an internal connection or path and following/sensing where it goes inside my body.
Don't know if any of that makes sense or relates to your question, but I tried.