The feats offer an obvious combo for classes with cold powers: Wintertouched and Lasting Frost. If you can keep hitting the same targets with cold damage, you'll always have combat advantage and do +5 damage, including with zone and ongoing damage.
That's a pretty major bonus, and I wouldn't have any problem spending the feats for it. What I'm not sure about, though, is whether it's worth focusing on cold-based encounter and daily powers to try to take advantage of it.
I've only looked into wizard builds in detail, and it looks like the combo would reach its peak at level 13 (it's only available starting at 11), when you could have Frostburn, Ice Storm, Winter's Wrath, and Icy Rays. That's a lot of extra damage you can stack up due to Lasting Frost, especially because Frostburn and Winter's Wrath both deal damage in the following round as well.
Even at that peak, though, there are issues. The cold spells generally target Fort, which (from a quick scan of the MM) tends to be one of the strongest defenses, sometimes higher than AC.
Frostburn is a decent spell, but Prismatic Burst seems like a generally stronger choice for the level-13 encounter spell. It blinds its targets, and you can keep them blind for an extra round with an orb.
Also, you only get extra cold damage when you hit the same target with multiple attacks in a row, so even intermittent misses can slow down the combo a lot.
So... is the feat combo truly a good deal, or is it just an attractive decoy? Also, has anyone looked into whether it can be worthwhile for a warlock?
That's a pretty major bonus, and I wouldn't have any problem spending the feats for it. What I'm not sure about, though, is whether it's worth focusing on cold-based encounter and daily powers to try to take advantage of it.
I've only looked into wizard builds in detail, and it looks like the combo would reach its peak at level 13 (it's only available starting at 11), when you could have Frostburn, Ice Storm, Winter's Wrath, and Icy Rays. That's a lot of extra damage you can stack up due to Lasting Frost, especially because Frostburn and Winter's Wrath both deal damage in the following round as well.
Even at that peak, though, there are issues. The cold spells generally target Fort, which (from a quick scan of the MM) tends to be one of the strongest defenses, sometimes higher than AC.
Frostburn is a decent spell, but Prismatic Burst seems like a generally stronger choice for the level-13 encounter spell. It blinds its targets, and you can keep them blind for an extra round with an orb.
Also, you only get extra cold damage when you hit the same target with multiple attacks in a row, so even intermittent misses can slow down the combo a lot.
So... is the feat combo truly a good deal, or is it just an attractive decoy? Also, has anyone looked into whether it can be worthwhile for a warlock?