As far as I can tell, this is not true. I was at the DMV 2 weeks ago renewing my vehicle registration (only cost $120) and the guy at the counter said I can keep my Michigan legal residency while having a CO DL.
Also, as far as both states are concerned, I can maintain legal resident status in Michigan which allows me to pay my state taxes to them ($0) If I'm wrong on this, then a few years down the road I might owe some backtaxes or something, but at my current pay grade, that won't be too much!![]()