Yeah, well, we don't have "much" multi-year ice these days, though. Most of it is FYI, is it not. Anyhow, i don't think it's of much importance, - be it -1° melt, or -2, or 0, or anything inbetween. Why? Because whatever it is, it won't change much in compare to say 2012 or 2015, especially when integrated over the whole basin (regionally it'll vary a bit from year to year because of somewhat different MYI/FYI combinations for any given region, sure, but still it's one very little detail me thinks).
So for the forum, i think it's good to settle that this specific feature of ice remains pretty much a constant, especially during any given season.