Hi Gang! I need to transplant my mature maiden grass and I'm wondering if I should cut the leaves down to minimize transplant shock and send the energy to reestablishing it's roots, or is it hardy enough to withstand transplanting, fully leafed out?

I think you will find that when you transplant, the grass will naturally die off some of the foliage. If it is still happy, it will stay all green. I would just let it do what it wants. Trimming when transplanting is more important with non-grass plants, and especially woody plants.

Edited for clarity.

Thank you for replying so quickly, Rick! The plan is to transplant this early evening.