You've got the crux of the idea, but I think when you are able to see all the items it will be more clear. Fundamentally, PvP gear will have lower stats then PvE gear (expertise excluded), including endurance. So high end PvE gear characters will have bigger health pools, but take more damage. The result of this interaction should get us to point of balance between the gear sets we are shooting for.
Thanks for responding. However, if I'm interpreting your response correctly, that means that top end PVE gear would receive none or next to none expertise. This, as you put it, would put us somewhere between "introduction bolster" level and top end PVP gear in power, but only on damage output. The damage reduction provided by expertise cannot be replicated by any PVE stats, and thus PVE gear would still be far inferior to PVP gear. Now, I don't think any PVE'er would try to argue that their gear should be equally viable in PVP as PVP gear. However, I don't think it's unreasonable to expect it to be at least competitive by performing as good as PVP gear a tier below it (i.e. DG, which is equivalent of EWH, performing at WH level in PVP). Thanks