Hi Doug, when I bought my troll used, it had the mtb crank on it, and I did remember your explanation from years past about the chainline--but this was my first bike not using square taper bb, it has the hollowtech external bb, and apparently to do a change from a 48/36/26 Deore to a 44/32/22 Deore using that type of external bb that doesnt have an axle running through the bb, apparently its an easy swap.
A friend of mine with a Troll did the change, from the stock 48/36/26 to a mtb one when he did about half of The Divide Ride trail, and while he had it done at a store, I seem to recall that it was straightforward according to him, although its very possible that some spacers were positioned differently for the mtb crank.

I know when I stripped my Troll down to the frame to give it a complete do over before my first big trip with it (put some Framesaver inside it at the same time) this was my first time disassembling and then putting back together a hollowtech bb, and it was rather straightforward. I had to buy a new bb tool with the right splines for the shells, but it went well overall and I didnt screw anything up.
I have a feeling that the 48/36/26 and the mtb cranks in hollowtech have very similar "chainlines", but I could be wrong.

The fellow on here named Gauvins has changed his 48/36/26 granny to a 22, so it certainly is doable. I may change my wifes 26 to a smaller one one day, but so far, with the 10 speed 11-36 on it combined with the 26inch wheels, the gearing is pretty darn good as is.

we are just about to get some double digit temp days here, nice change.
cheers