How do you define (meaningful) choice?

[AmiableApkallu]

Ruin 2 has some cases where it is the better choice (situational) than Broil IV, and Broil IV has many situations where it is the better choice. But there is some gray area where it's up to the user. A tight movement where you MIGHT be able to get in the Broil, but the player might deem it too risky and go for the Ruin 2. This is still a meaningful choice since there is a choice and which answer is right isn't necessarily a set thing.

As you've phrased it, the correct answer isn't a set thing only because you've neither precisely formulated the question to be answered nor precisely formulated the criteria by which potential answers are to be evaluated:

• If the question is, "which action maximizes DPS for this GCD, everything else be damned" and it's theoretically possible to cast Broil IV safely, then the correct answer is Broil IV.
• If the question is, "which action is expected to maximize my personal DPS for this GCD" and there is a 220 / 295 ~= 75% chance or better of casting Broil IV safely (where "not safely" means, say, tanking the floor), then the correct answer is Broil IV. Otherwise, the correct answer is Ruin II.
• If the question is, "which action maximizes the party's DPS for this fight" and there's a non-zero chance you might wipe the party if you cast Broil IV, then the correct answer is Ruin II.
• Etc. Etc.

The choice between Broil IV and Ruin II here isn't meaningful because you're trying to choose between the actions themselves. It's meaningful because you're trying to decide which question you actually care about, and then trying to answer it with imperfect knowledge (do you really know what your chances are of pulling off a Broil IV are?).