I'm just going to bump this to illustrate/discuss a couple of things.
1. People see things very, very differently when the team is losing.
2. You give your starter every chance to battle back if he's got a chance to be ready. That's their right, especially after Geno had that performance against Dallas before going out. Let him try to work back in. If he can't go, you've got a capable backup who has been in your system for 2 years now.
3. The coaches provided an excellent structure for Lock to operate within. This was a textbook "How to win with your backup QB" clinic.