IMO if patients have CVD or multiple risk factors insurance will cover R-IT label without much protest, especially if they know from their own records patients are taking a statin and for example a BP med or diabetes med. Which leads to your next question - if TGs drop below 135 after a patient starts V, would insurance coverage stop - no, and I'd say "absolutely no" - that would be akin to someone who needs a BP med being denied coverage because the drug worked and their BP went back to normal levels - as soon as they stop taking it, BP will go back up because BP meds are band-aids, they treat symptoms, not the cause. Without a firm MOA for EPA (and there may be multiple MOAs), same thing goes for TGs.
Per FDA telling docs how to practice medicine, they can say whatever they want, but it's pretty clear the inertia of prescribing habits is hard to overcome - 6 yrs after FDA debunked fibrates and niacin for CVD at ANCHOR AC they're still being prescribed and sold at very high levels, especially fibrates. You make a very valid point that managed care all-in-one systems drive prescribing habits maybe more than anything else - docs are given bonuses for keeping drug costs down, even if in the long term it may end up costing the insurer more money (like denying V then later having to pay for an MI).