I think it does, or at least that's what I understood when Naughtykutchy said "They either focus on this one or we're looking at more +6 months per update if not more if the story starts to branch out". They already said that thanks to one of the benefits of their collaboration (focus on each other strengths), any possible delay in Radiant's development isn't or won't be due to having several projects in parallel but other reasons... that well, shit happens.Nice post...but don't believe anyone actually disputed this. However, everything you mention, just adds to an already exisiting issue of doing too much in the first place, which is only compounded when life rears its oft ugly head.
And I think one of the things they considered before starting the collab was whether what they wanted was too ambitious or whether they could really handle it. If after doing the pros/cons they decided to develop Radiant together + continue with their solo games it's because they see themselves capables of doing it. Maybe some of us could see it as you say, doing too much in the first place, but it's just that even if they were dedicating exclusively to Radiant, all the misfortunes they've been having would still be there, so there's no reason to say they're burning out for being too ambitious. At least until now.