I am surprised that we don't do this more. In Ollie's defense, we usually have 2-3 of our bigs in foul trouble which prevents him from using the big lineup.
I love Giffey, but the 4 just doesn't suit him very well. Daniels at least is an excellent shot blocker and a mismatch offensively against most 4's. He's just not strong enough to defend stronger guys in the post without fouling.