Surecast Enhancements, Please!

[kyuven]

So the point stands that it is still very situational, but it does feel good to negate an interruption from a huge attack that would otherwise interrupt you.

Except all those interrupts can be prevented by just timing it so you're not casting when the attacks go off. It's not like they're rapidly going out in a short period of time, no single big huge interrupting ability goes out more than once a minute or so.
Most of those abilities have a 10 second wind-up time, while your own have around 2 seconds or so.
Add to that surecast only affects one spell, which means you need to tack on another second or so to your cast times just to use it then start casting. Swiftcast works a lot better for this.
And as mentioned if you're a healer, you should be setting your buffs and damage mitigation abilities BEFORE the big attack goes out. Which again, you have about 10 seconds to prepare for.
Surecast, when looked at in a vaccuum, isn't a bad ability on paper, it's just useless when looked at side-by-side with Swiftcast.

[Mendalas]

Except all those interrupts can be prevented by just timing it so you're not casting when the attacks go off. It's not like they're rapidly going out in a short period of time, no single big huge interrupting ability goes out more than once a minute or so.
Most of those abilities have a 10 second wind-up time, while your own have around 2 seconds or so.
Add to that surecast only affects one spell, which means you need to tack on another second or so to your cast times just to use it then start casting. Swiftcast works a lot better for this.
And as mentioned if you're a healer, you should be setting your buffs and damage mitigation abilities BEFORE the big attack goes out. Which again, you have about 10 seconds to prepare for.
Surecast, when looked at in a vaccuum, isn't a bad ability on paper, it's just useless when looked at side-by-side with Swiftcast.

I try to save swiftcast as a whm if I can since raise is such a long cast. If SC is down when somebody dies, well that just sucks.
Also, besides single target casting stoneskin on everyone (waste of time and mp mid battle) there is nothing else I can do to get ready for a big attack that interrupts casting. But I can time it with surecast to heal just after the damage is received. It may not be totally necessary, but it sure is rewarding when you time it right. This is not to say that I don't partially agree with you about surecast in general, but it is helpful on white mage in most fights for healing up as fast as possible when an interrupt is inevitable.

[kyuven]

snip

See, in my mind this seems...off.
For 4 man parties...let's not kid ourselves it's completely and utterly useless if everyone's doing their jobs right.
But in 8 man parties, you have a scholar most of the time. Before those big AOEs, I always see Stoneskin thrown out if possible and maybe a medica 2. Most WHMs i see take that gap of time to ensure they have enough MP for the next phase that's coming (since these attacks almost always coincide with phase changes)
But the important aspect is relying on the scholar for the set-up, while the WHM handles the "denouement" of the attack. And if speed is an issue as WHM you also have presence of mind to make use of.
And the interesting thing is there are just as many situations where these attacks are followed up with an add spawning (t13 gigaflares/rage of bahamut, weird timing in Leviathan) so having your heal go off in time with the attack could be a BAD thing, something i've seen happen in t13 more than I'd like.

[Mendalas]

TLDR

It sure does feel good though to not get interrupted when generally you would. Feels like I'm cheating or something haha. But in all reality, I would definitely agree to an effect change for the ability overall. It was meant for PVP. But who knows maybe in HW there will be a lot more situations where it is useful.