So I've recently become a believer in adding a pinch of salt to my buttercream based on everyone's posts here, and wondered if you can do the same with MMF to cut down on the sweetness... I wasn't sure if it would affect the consistency. Has anyone tried it?

IT WORKS!!! I have done it!

It doesn't change the consistency at all. But, I have learned here on CC to use popcorn salt instead of table salt in all of my icings, because it dissolves faster. I put about 1/2 tsp. per batch of MMF (16 oz marshmallows). I put it in while I am microwaving the marshmallows to melt them. (As a side note: I also replace the 2 Tbsp water with 1/2 tsp vanilla + 1/4 tsp butter flavoring + water to = 2 Tbsp...tastes great!)