I personally think that the scheme Philbin has brought in is very sound and has a lot of potential for being able to overcome a lot of different defensive looks, but it seems like it needs a very wide ranging skillset that a lot of our current players just dont have. Chuds offense does put a lot of pressure on them, which magnifies the problem, but I think there are deeper issues at work as well.
We seem to run a mix of Man/Zone blocking concepts and have a mix of players who excel in either one or the other, but very few who have the skills for both (only AC/Kelly, if anybody). The problem that arises is that we will always have players on the field who are not playing to the scheme that gives them the greatest chance for success. When we run a zone play, our slower/stronger players are at a disadvantage and when we run a man play our athletic/weaker players are at a disadvantage.
Part of the problem is that they dont have the proper personnel for one or the other (which isnt really Philbins fault) and he seems to be trying to figure out a way to make it work. Its not really working, but you have to give props for trying to make due with what hes got, especially considering all the new faces coming in due to injuries and the fact that the OC insists on making it as hard as possible for the OL. Its not an easy job and hes at least trying to make adjustments, which is more than we can say about any other coach on the team.
It seems like it would make more sense to start by constructing a line that can do one scheme really well before we start trying to put square pegs in round roles. Especially with a lot of young guys in the mix.
If we get a young group of lineman that all excel in zone blocking, it doesnt mean that they cant eventually work in some man concepts once they get comfortable in their zone skills at an NFL level as a unit, and have some time to work on strength programs with the trainers. The same goes for if we started with a group that was more suited for a man scheme. We could work in zone concepts after they have time to get comfortable in the man scheme and have time to work on conditioning/ shedding a little weight if necessary.
TL/DR: I think Grigson was a bad GM and wouldnt commit to looking for OL to fit any particular scheme, which has left Philbin in a tough position trying to pick up the pieces and make it work. Injuries and Chud havent helped either.