Maybe they should actually make use of WAR's self-healing abilities in a raid fight one of these days... Make a fight that's less tankbuster focused and just has a very high average DPS, so you need much more sustain and mitigations are slightly less useful since you can't have 100% uptime on those...

But personally, I don't think tank heals are ultimately the main problem... It's that Healers aren't given anything else other than heals. We're the lowest DPS jobs, and our gameplay outside of the bloated heal kits revolves around mashing 1 button. Even if they took away all the self-heals from tanks, the end result would largely be that instead of spamming Glare, it'd be spamming Cure. Or other Jobs equivalents...