I do - I incubated all last year, basically every three weeks.  We've not been using it because we have too many chickens already, because running the microwave while the AC is going trips the master fuse (so we've been trying to cut power use) and because anything that generates heat inside the RV while the AC is struggling is to be avoided.  But yes, I could incubate in the shed (and plan to) if any of the eggs are still viable.
[and that's a reminder I need to dig thru the shed, see if I have a replacement fuse or two, since its possible these old tandems have tripped so often that they are starting to trip prematurely.]
Culling the darker red roos is part of reducing flock size, too.  I already have hens with bare patches - if I take a number of black hens out of the mix, and don't continue to shrink the male population, it will only get worse.  and I've already culled the Roos who had other undesired, so now its just picking between reds...