The official brochure for navigating roundabouts specifically states "do not change lanes..as you exit"...therefore, if I change lanes to get in the RESIDENT lane, that is a violation of traffic law. (as in the OP, there is no legal way...)
http://www.districtgov.org/community...t-02-08-12.pdf
What if we all just forget whether the gate says visitor or resident, and stay in the legally designated and safer lane: inside for a left turn, outside for a right turn?