It does benefit the plants and I can see how foliar spraying them would be advantageous. For one, by spraying as opposed to drenching, spraying you don't have to worry about ph or N-P-K calculations in your final solution. Say you are dialed in with a particular N-P-K. When you use pro-tek, being so strong, almost 0-0-4, you have to take it into account for your final value. . Also, foliar feeding is a much more efficient delivery method. Spray the undersides of the leaves to reach the stomata. You should experience the same benefits: A stronger plant with better heat tolerance along with increased pest tolerance. I would be very conservative though and also test one or 2 leaves before you commence to spraying the whole plant. Pro-tek does show directions for foliar feeding on the label.
When I use AN PH-Perfect, they say no non-Ph perfect sups should be added to the soup or else it will disrupt the buffering chemistry. Hell if I'm paying an exorbitant amount for some weak ass .15% silica Rhino Skin which is PH-Perfect. By foliar feeding, the silica is delivered without messing with the soup. Problem solved.