I don't think SE consider D4 RDM in the mechanics in this patch

[Carighan]

So long as fights proceed on strict timelines, it doesn't matter how jobs are designed. For any given encounter, you'll still be pushing your buttons in the same order every time. The fact that one encounter might need one order, and another encounter needs another order, doesn't change much.

You're right insofar that the existing random elements of Red Mage ought to have a bigger impact, precluding knowing that you'll generate enough energy to run the odd combo and the double combo every time. That might happen. Or not. But with a by-now 40% proc chance IIRC, that just evens out too much. An easy fix here would be to reduce the chance to 15% or 20% to get a proc, but increase the energy obtained from a proc by 100%-125% to compensate. Same energy gain over time, but it might be utterly skewed.

And again, this focus entirely on static rotations in job design is the problem. It needs to go. It precludes designing interesting gameplay in the first place.