McGee did not retire...He wants to still play in the NFL. I think there is a big difference. May be when McGee eventually retires, they will do the ceremonial sign-and-retire and do all the stuff you described.
I think with this regime, nothing is guaranteed. If a rookie does outplay Lindell in training camp, I think Lindell may get cut. After all, even last years lousy regime cut Moorman during the season. If cutting Lindell saves money and a younger player, I see this group taking it that way.