Are you going to split the wort in half? then fine, i do that all the time to see what the tastes of the yeast are. But should you add them both together no, I wouldn't do it that way, unless it's a hung fermentation. The WL380 is a great yeast lots of Hefe flavors ( lot's of banana and clove) make sure you use that yeast at ferment temp of 62 degrees f to max out the flavors.
