Before the speculation got out of hand I just wanted everyone to know that I believe that C-Mac is the MLB of the future for the Titans and when he is healthy he is one of the biggest spark plugs in the NFL. Since he isn't healthy the Titans most likely have him taking snaps with the second team because the first team sees such a high volume of snaps that it could make it risky for his recovery to go full-speed through that number of reps. Instead, he can take mental reps with the first team and still make strides physically without putting himself at risk.
However, since the Titans have no reason to put McCarthy through a high number of reps, they made the right choice putting Fokou with the first team on the "meaningless" OTA depth chart. Quite frankly it is almost necessary for the Titans to figure out how well he can play considering McCarthy's injury history.
Another reason that Fokou gets the nod is because he needs to learn the blitz schemes that Gregg Williams is teaching the linebackers and with the addition of Zaviar Gooden to the linebacking group, it is much more likely that he will be primarily the backup for McCarthy.
Fokou is a former seventh round pick that has never really found a home in the NFL. In four years Fokou has bounced from Philly to Indy and now he has ended up in Tennessee. Over his four years he has played at every linebacker spot in both the 3-4 and the 4-3 defense except as an edge rusher.
It will be interesting to see how Fokou does with a solid supporting cast and (basically) two defensive coordinators putting him under a microscope.