This is interesting to me, because I have never not used whirlfloc since ive been all grain brewing. I've always questioned this fluffyness. I'm thinking this explains the reason why I suck at whirlpooling lol. Essentially, I don't suck at it, but the whirfloc could possibly prevent the trub from coning up? Does regular irish moss have this affect on trub too? If so, I'll just continue to use whirlfloc and continue to filter with the sock.