Stan, I don't know why folks are beating you up on this. I have seen this exact thing many times in many flavors. Dimetraxia casts, a troop has 2 life left and is burning, but the burning doesn't "stick" and they live. It seems to happen more often with trait-generated status - Jarl's burning and Mab's frozen are the ones I have noticed.
Others have alluded to a "guaranteed stick" for 1 turn, but I have never seen that. Maybe there's an RNG glitch that makes is 1% instead of 0% for the first turn and +10% after or some such, but it does dispel on first turns.
Whoever said that this wasn't in the patch notes didn't read the patch notes very carefully. It is very much in there. Yes, death mark is a pain in the butt, and I am glad to have this fix after a 4x insta-kill by a Death Curse. That is just too crazy, so I approve the change to give you a round to deal with it. However, to SaintLevitan's point, it should now stick around for an extra turn to have a chance of activating.
All that said, I completely agree with the original post. Status effects (besides death mark) do not have a big enough impact on the game. If I play a troop with cleanse, it is almost by accident: Celestasia on Whitehelm week or on a Dragon team where I need yellow-blue, most likely. But the status effects do need a bit of a buff, and I think this is a good compromise without unbalancing the whole apple cart.