Hi Michael and Everyone,
I've got to make a few top bars like yours Michael and try them out.
One factor I hadn't considered in these observations was the change in my top bar width. Last year I used 1 1/4". The bees centered the broodnest comb on those top bars with very little problem.
This year I used 1 3/8". DUHHHH! Somehow I forgot about that change. That may be a bigger factor than the method used to guide the bees. Michael kept mentioning his top bar spacing and I spaced it out! DUHHHH! :> )
Thinking 1 1/4 in the broodnest might make most of the difference.