Love how any feature that offers even a 0.0001% boost to someone's character power becomes "mandatory" and "necessary".
I only run LFR, due to work schedule, raiding is out of the question (4pm-12am, Mon-Fri = Not gonna work). I got my Relic of Xuen and my Sha-Touched Axe both upgraded. That is all I plan to do, cause nothing else will be sticking around as long frankly.
The feasibility of upgrading all your gear, as the mandatory crowd will argue, is out of the question. It takes just short of 6 MONTHS to do that. The only time we might see a content cycle that long (that you also won't have other things to spend JP on) with the timeframe they are working under in MoP, may be between Siege of Orgrimmar and Expansion #5.
5.2 rolls out. VP is downgraded to JP (as the usual happens every new tier). Are you gonna spend VP on Upgrades of your Normal Epics from your first week of raiding, or saving up for the new 5.2 Faction VP items? Right there, you can likely void 4-6 weeks (or more, depending on slots) of VP gains from being applicable to upgrading. By then, if you are "serious about raiding", you will be plugging away in Heroics, you aren't gonna spend a drop of VP on anything that isn't BiS, which you may have little to none of yet, depending on level of progress.
People arguing about "mandatory work we are forced to do to be better". It's a GAME. Have some FUN in it, and don't be all about the math and numbers. You'll realize how much more enjoyable it can be, when you don't try to consume every ounce of content immediately.