Ref. the comments on letting the bees fill the brood areas and then
simply extracting from these areas. The only thing which makes me uneasy
about extracting from brood areas is that since the arrival of Varroa
and "chemicals", the brood areas are likely to be the most "chemically"
area, albeit most of the chemicals should be in the wax. In principle I
therefore disagree with brood area extraction, but it's a choice.
We  always go for cut comb so the honey has to be in the supers. I agree
with the comment of loading up the brood area with advanced brood in the
middle and later brood at the edges.
Murry's quite right in saying that there's nothing like having plenty of
bees at the heather and the worst thing that can happen for heather
preparation is a poor (wet) June where the bees shut down laying (as
happened here this year) -the only solution for that is to feed in
June/early July.
Alan Riach
Bathgate,Edinburgh,Scotland