Lately (since November) I've been brewing session beers. My big beer is 1.050 lol. Most finish about 3.5-4% abv. Last fall I bought 3 pounds of carapils. I currently have 2.5 pounds left. I used it once, haven't used it since.
I don't need it because I don't use adjuncts in small beers. (Not afraid of flavor I guess) My premium lager is 8 lbs pils 2 lbs Vienna. No head problems at all.
I was listening to a February 14 episode of BN Sunday Session with Dr Bamforth, who says he's been wrong about caramel malts. He now knows that many caramel malts are foam negative. The lighter they are the more foam negative they are.
In my opinion good process all the way through is what gives you good foam. Poor process, or hight % of adjunct sugar, or high fusel or high abv will reduce foam.