In veg you can possibly get away with it, if sprayed infrequently, but what do you do for the rest of the day? In flower though, likely keeping a mist constantly going or on every 5 minutes (what you'd have to use to keep the ladies cooled by evaporation) is a bad idea. Especially in high humidity areas. Inhibiting the plant's natural aspiration and transpiration isn't a way to keep 'em cool.
Many times in the past I've sprayed in the morning, and come back later that day...and the moisture is still trapped between overlapping leaves.

As far as water droplets acting like a magnifying glass:
Water-Drop Magnifier - Optics
Droplets slowly evaporate. (and get smaller) "the smaller the drop, the greater the magnification". (from the above link) We're not talking a 'high heat causing combustion' focal point, just enough heat to do damage to leaf tissue. Add this to ambient heat and direct lighting. No, spraying is not the optimal solution.
Rusty Trichome Reviewed by Rusty Trichome on . Should I cut these tops? Hey everyone I'm into like third grow, so though I've done a good amount of research BUT.......... My first three were very successful and I try to keep it pretty simple and follow directions for ferts, but I think I went over board on nectar and foliar spray once. I HAVE SIX WEEK OLD COLA'S ON AN ICE PLANT AND IT WAS BEAUTIFUL BEFORE I SPRAYED IT WITH FERTS INTENDED FOR ANOTHER WW PLANT NEEDING CALMAG+ (GUY AT HYDRO STORE SUGGESTED SPRAY N GROW FOLIAR FEED INSTEAD). ANYWAY, THE TOP Rating: 5