Use of Mark of Subversion?

What's the point really? Compared to Power Spike it's worthless as is compared to Shame/Guilt, both of which are better for anti-casting. So in what situations would you use Mark of Subversion?

possibly if your not playing a mesmer (secondary or primary)

I used this skill a bit as a necro and it helped guarantee a monk kill when I targeted for my guild in tombs.

It's actually comparable to Shame now that it's had its energy cost toned down. Casts and recycles faster, costs less, but doesn't hit quite as hard. If I was heavily into blood for some reason I'd run it.

Peace,
-CxE

I made a build with shame, mark of subversion, backfire and soul leech plus some interrupts and energy drain that worked very, very well. You have 4 options for preventing casting over ~10 seconds, so you can effectively work on two healers at once. If there is only one mork he can expect to have the 4 above spells on him at different times with some overlapping of backfire and soul leech cause leech recycles so quickly. The best use I found for mark of subversion was to finish off a healer who was being focused. Get him down to ~100 health and hit that, if he tries to self heal he is dead. This works especially well if the other monks on the team are incapacitated with backfire or shame or being interrupted.