I think the best chairs are those that force others to justify their comments and present an alternative view. That was THE moment of the WC for England and Seedorf, Henry and Rio were able to simply state that a defender should have been anticipating Gerrard's mistake and that he was in no way responsible for the goal conceded. With that sort of unanimity over something so ambiguous it was Lineker's duty to jump in and offer an alternative view...especially if that was what he actually thought was the cause in any case.
People/viewers respond to that and it strengthens the chair's position. Instead, Lineker just rolled over and left the defenders to carry the can.
I agree with you that they should....but they rarely do. I think its ridiculous for the panel to suggest (in particular) Jagielka could've anticipated him making a balls of the header...when he should've left it well alone. This p/poor level of analysis is why I don't watch them.