Debating scrum decisions with props is asking for a baleful stare or sustained silence.
Listening to their viewpoint is a far safer proposition unless you have been part of the cauliflowered collection.
Occasionally they are left in limbo and All Black loose head prop Tony Woodcock was quick to check referee Nigel Owens' decision late in the second test.
He ruled in favour of the All Blacks, a verdict which earned him the ire of Ireland but got the hosts on a roll towards their defining dropped goal.
"You'd have to ask the ref really but to me it looked a bit like a whip wheel rather than a push straight through but those things can go either way," Woodcock said.