I have followed all this discussion about queen excluders, and have
written about this before (see archives: subject=excluders, with
author=tvf).  The point I wish to emphasize here is that swarming is
really unrelated to the presence or absence of excluders.  To use
excluders rightly, the queen(s) should be young (best with newly
requeened colonies), the brood nest should be "boiling" with bees and a
good honey flow should be starting.  Then above the excluder you can
give one super with foundation (plastic works fine) or with drawn comb,
and watch the progress for a couple weeks.  When they start working it,
give another two supers on top.  Repeat as necessary as long as the flow
continues. The only caution is that a super of foundation usually is not
drawn when placed four or five supers above the excluder, and maybe that
is because by then the flow is often slowing.

I have never put brood above the excluder (unless setting up two-queen
units) and never fed syrup when supers were in place.  The latter is
dangerous, possibly allowing excess syrup to be stored in the newly
drawn comb, and thus adulterating the honey.

Ted Fischer
Dexter, Michigan USA