Here is an idea I had a long time ago that I think someone should have a go at. The overhead dust collectors cannot help but miss some of the fast moving chips that head away from the intake. After all, there is no way a flow driven by a <15 lb/sq in pressure difference (vacuum) can stop the high speed chips from a 20000 rpm bit. These chips have to be physically stopped before they can be sucked up. That is why the Dust Cap and the Dust Shoe work so well - they physically stop and contain the chips. Why not use the dust shoe idea to block the chips and to redirect the chips to the intake of the RingNeckBlues collector? I have attached a simple cut down of a Dust Shoe for you to consider the point. The shoe has no pipe and fits under the bit plate. Very simple, just bolt it on. With a half a brush, I think it could make a big difference.
Take a look at the mpc and think about it. I do not have a RNB collector to experiment with. One of you guys could take this on and see if it might work. Feel free to use or chop up any shoe mpc I have posted. (I do not think the attached mpc should actually be carved, I only chopped up the shoe to demonstrate the idea.)