I agree that Mennenga (can we fix the spelling of his name in the title??) should probably be let go, but two critical things need to be in place for that to happen:
1. The head coach has to be strong enough to do it
2. You actually need to have a better, capable coach ready to take his place
Matt LeFleur has been pretty good at his job so far. However, terminating someone's job is a completely different animal. Unless you are the president who takes pride in firing people, most people find it difficult on a personal level to do it especially for the first time. You can all blather about how it's his job and what-not, but my guess is that the majority of forum posters have not had to personally look someone in the eye and tell them that you are firing them from their job. Unless you hate the person or they deserve it for misconduct, it is hard to do. I am not questioning LeFleur's ability, but merely pointing out that I don't think that he has fired anyone yet except for when he first became head coach....letting Mike McCarthy hold-overs go.
Second, I don't know one thing about Assistant Special Teams Coach Maurice Drayton or ST Quality Control Coach Rayna Stewart. They look like good guys on the Packers.com website, but its possible that they are 100% in-step with how Mennenga runs our special teams. If LeFleur isn't confident that one of those guys can lead the group through the rest of the season, then who does it. Most special teams coaches are employed with another team/university right now.
Firing Mennenga is one thing, but replacing him with a better coach is the key. Firing for the sake of firing is knee-jerk and ridiculously stupid.