> My advice has always been to inspect frequently and learn what normal looks like so you can recognise abnormal. Technique may play a part as there's obviously a difference between gloveless and gentle compared to full suit of armour and bashing them around.

I advise the same. The more often people are in hives, the higher their skill level and the lower the negative impact. Besides, interacting with the bees makes people more conscious and more appreciative of them. 

I cite below studies that show the negative impact of hive manipulation on honey bee health, but I still maintain that a conscientious beekeeper does more good than harm. Let alone beekeeping is called "bee having." 

''Some beginners think that bees can muddle along by themselves, and that all they need do is to put on a super during the flow, and then watch the bees at work and rub their hands."  Bee World 20.1 (1939): p. 12.

See:

Oertel, E. "Colony disturbance and nosema disease." Journal of Apicultural Research 6.2 (1967): 119-120.

Fries, Ingemar, and Scott Camazine. "Implications of horizontal and vertical pathogen transmission for honey bee epidemiology." Apidologie 32.3 (2001): 199-214.

             ***********************************************
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