A RDM Equivalent to BLM Triplecast

[Sylvain]

Actually I think Reprise is that Triple cast like ability. Essentially, you sacrifice / delay a melee combo in order to move. Some people will try to play around Dual cast, Swiftcast etc, and some might choose Reprise (which has an impressive 300 potency for now).

Reprisal is definitely RDM equivalent to Triple Cast (albeit more simple to use as it requires no CD management)
As said, RDM already have enough mobility with dual cast + Swiftcast. The addition of Reprise is, I think, mostly aimed for less skilled players.
In any case, it will be better to delay your melee combo than do nothing for an entire gcd.

Strictly speaking, at higher level of player I would say Triple Cast is better because you can use it both for mobility and a slight dps boost (around a third of a FireIV... nothing fancy but it's better than nothing). But having coached many BLM, I can tell you most have no clue on how to use it and how to properly manage their proc for mobility.