This is an interesting question and I'm curious to see what others say. I am a total meat bird newbie, but in the horse world, some say the mare can have a greater impact on offspring than pure genetics would warrant, since there are factors during pregnancy (i.e. larger mare may give birth to larger foal) and also afterwards, in terms of the offspring learning behaviors from mare and her temperament shaping that of foal. I'm wondering if having a hen that's a more aggressive forager would result in offspring being more inclined, for example. Anyhow, fascinating topic!
HA, I'd be careful not to espouse that notion anywhere near folks who got burned up with the genetic horror of IMPRESSIVE. and that he was.