>Large clusters eat more need more resources  than small cluster less prolific bees.

This is true, mostly because a strong cluster will end the broodless period mid Jan or earlier
A truely cold-climate adapted bee will delay for a month or more
A large cluster is quite efficient at retaining heat, so will eat only slightly more 

I have had queens who recommenced laying as late as early march

If you are a northern beekeeper and your bee yard has electricity available,, 
then I don't know why you would not install hive heat
Costs about $1/month, well worth it, set thermostat at -5C or so

Presently in Thailand, far too hot,,
have no idea how well my bees are doing
Any Thai beekeepers monitor this list?

dave

             ***********************************************
The BEE-L mailing list is powered by L-Soft's renowned
LISTSERV(R) list management software.  For more information, go to:
http://www.lsoft.com/LISTSERV-powered.html