I think too much is made of not doing quick checks early on. We find alot of problems can be resolved quickly. We don't do full inspections, just a quick check for food, space and anything else obvious often saves colonies in my experience.
General rule for us, is if they are flying freely, then a quick early check in March helps alot. Obviously, we only do this when the weather is forecast to be warm the night after.
Seems to work for us....and goes against the "wait untill the shirt weather" mantra.
As said above, we also had one that needed to be put into a nuc from a full hive...which we did. They will do much better as a result. They were flying alot more vigorously a few days later collecting more pollen. I believe this is due to the pheromone given of by brood that stimulates foraging. If its in a smaller more condensed space, I believe it helps concentrate the pheromone which stimulates more foraging. Certainly the bees went from just milling around d to vigorously foraging withing 24hrs.