This triple is on my tandem. It was a little tricky to get adjusted, but it is working well now, except for one thing. I use the middle ring a lot, and it is my opinion that I should be able to utilize the entire cassette while in the middle ring. Do you think this opinion is correct? Specifically, I like the combination of the middle ring and the largest cog for climbing many of the grades in my area. However, I get bad interference in that combination. I don't consider this combination to be "cross chaining", but, is it? Thank you!

I think I've got to change my shifting strategy. I view my triple as a double, plus a bail out gear. I utilize the little ring only in a really difficult climb. I think I have to divide the cassette into thirds. The little cogs for the big ring; the middle cogs for the middle ring; and, the big cogs for the small ring. That would mean I would use the small ring a lot more than I use it currently.
Does that make sense?

I'm not an expert by any stretch, but I ran into a similar situation on my road bike. I ended up setting the FD so that I could ride the big rear/middle front combo without rubbing. If it rubs on the small cog, so be it; I just stay in the next cog or change up front.

you may be able to alter the chain line a little to improve the alignment but you may get better answers to that tn the tech forum.

swapping cassettes or chain rings around to alter the gearing may help too...