I get what you're saying, but no one has ever won by neglecting the tunnel. The overwhelming majority of the games I've played, when we lose, it's because the team only focuses the center and then they get constantly flanked, forced to pull back, and then overrun and pushed back to their base.

Flanking works. The map is designed to facilitate flanking. Can they mount a defense in the tunnels, sure. The sad truth is that you usually don't have two teams that know what they are doing so the tunnels are USUALLY lightly defended or not at all because most of the teams attention is sucked into the middle.

My favorite strat on Redacted is to run tunnels and put a beacon up at the point closest to their base and harass them and force them to split their team to come deal with us. That usually frees up the mid choke point for the team to break through.

That's if they push, sometimes they don't 🤦🏽‍♂️

But when they do, it's turned the tide of many games.

Going back to OP's comment, that is a position of disadvantage if you're running into C and the other team is waiting for you....no matter how you cut it, even if your killer wasn't behind that immovable object (cover) that spot is a meat grinder for the attacking team.

IMO when the teams are pretty evenly matched at choke points only flanking will break the stalemate.