When I gig with my Mesa vertical 2x12, not only do I have a beam blocker on the bottom V30, I replaced the top with a G12-65 for more beef and smoothness and I always ask for some flightcase or crates from the venue to raise it up a bit more.
That way you're less prone to dial in your amp overly trebly as some would when your cab is too low. Soundguy more happy and the audience will suffer less. ?