@Stufoo,

Read carefully, its not like the current Sentinel...GLD Ability 1 (from the reform notes) specifically says: "...and increases enmity generated by actions executed while effect is active."

Now let's look at the current way Sentinel works: Short duration (good for an incoming known timing blast attack IE: Ifrit's attack, or any boss attack for that matter; which is why the dev's I am sure are getting rid of this ability in the sense of how it current works). Now back to the new ability, it increases enm gained while under its effect, this leads me to believe that we are looking at an ability that lasts for a longer period of time, to help with tanking, hell, GLD Ability 1 could be Defender. Actually after relooking at the MRD abilities, I would say GLD Ability 1 = Defender and GLD Ability 3 = Rampart.

But to recap:
Current Sentinel = short duration, large damage reduction
GLD Ability 1 = mid-long duration, increase enmity, unknown amount damage reduction

therefore Current Sentinel =/= GLD Ability 1