Threat set dilemma

[Stompya]

Here is the question:

I got 2 pieces t9 (shoulders and gloves) and am thinking wether it would be a good idea to combine them with 2 pieces of t8.

But, since I never had the damn t8 legs drop, the only 2 pieces I can use for this are helm and chest, and those would result in a massive loss of expertise from my current ones (hauberk of towering monstrosity and headplate of the honorbound).

Does anyone have experience or has made some parses to check if the resulting tps boost from the 2 bonuses combined would outbenefit the loss of expertise?

[Kazeyonoma]

Chances are if you have upgrades, you take then, the double set bonus is good for gimmick fights where you need to chase dps as a tank, but I dropped the double set bonus and never looked back. Survivability = #1 priority if you're working on heroic TotGC

[Stompya]

I know Kaze, I think my question came out wrong.

What I really wanna know (for gimmick fights like Hodir hardmode) is, which would result in better threat, the 2+2 tier combo, or just the massive expertise on my current pieces?