How much pressure?
I admit I am very new to the game so please take these thoughts as questions more than opinions.
I use a very simple set up of a straight piece of flouro typically about 8-10' long ranging from 10-20#s in strength. I have not in my experience had a problem getting the fly to turn over and not yet being an expert in knots makes for less to go wrong.
With that said, in the few experiments I have read about and tried I don't think it is possible to get anywhere near more than say about 6lbs of pressure on a tippet using a fly rod. So, with the exception of using a short section of bite guard for blues, albies etc...why use the heavy stuff. I think what you really loose is fly action in doing so. With heavier tippets I have found that the fly looses the wiggles and waves you work so hard to design in your fly which is I think the biggest attractor in your presentation.
Just another perspective.