Nessuno,
It is not certain (yet) that changing sprockets on a DCT equipped AT will be any more troublesome (by interfering with the DCT computer and getting trouble codes) than on a non DCT bike. Honda would be pretty shortsighted to build a bike that goes against a time honored tradition of changing sprockets and tire sizes on motorcycles - especially dirt bikes. But even so, there's not enough known about how the DCT operates yet to reach a conclusion. We will have to wait to see how it plays out. Perhaps you will be the first to find out.
As for optimizing the DCT to be a Jack of all trades, I don't know whether that's the reason, but they do have slightly different ratios for gears 1 and 2 and the reduction ratios on the NC700 than the NC700 DCT bikes. Maybe this will be helpful :
NC700X/XA-------------NC700XD:
1st 2.812----------------2.666
2nd 1.894----------------1.904
3rd 1.454----------------1.454
4th 1.200----------------1.200
5th 1.033----------------1.033
6th 0.837----------------0.837
Reduction ratios: NC700X/XA 1.731/2.687
Primary/final NC700XD 1.921/2.437
NC700X/XA/XD all use 16T engine sprocket
NC700X/XA - rear wheel sprocket 43T
NC700XD - rear wheel sprocket 39T