Steve,
The Mountain Camp method is twofold.
One, is a food source if the bees get to the top and run out,which sometimes they chimney up through the center and find themselves too far from the honey at the outer edges.
Two, The sugar is a dessicant of sorts as it will absorb moisture rising to the top of the hive.
Both options more relevant in a cold climate, like you were saying about location.
Another thought, how long until your flows down south? Early feeding is not necessary unless it's for survival(lack of stores) or brood buildup in anticipation of a flow 4 to six weeks out. Feeding for the sake of feeding seems unnecessary.