All opinions, but I see it the other way round. I think McCarthy especially may press high or look to break forward, but more often than not when he obtains possession he gives it to Barry to try and make the switch, open the game up, play to Roms feet, bring an advancing CB into the game etc etc. The reason Barry plays so deep is he is comfortable taking the ball from anyone in defence and is intelligent in making angles to receive passes from them. Ive never thought Martinez sees Barry as a typical, snappy David Batty type who's primary function is to win the ball.
I've been wrong before though. Lots.
Nah not saying only/primary function is to do that, but it's vital for the way we've set up (with the attacking full backs and all) that our two defensive mids defend a lot more, because of the open space left by the left and right back respectively.
Because of the way we play as well, though - it's vital for them to be able to actually pass, not just break up play. That's similar to a deep lying playmaker/regista role in that way only. Pirlo was usually very much relieved of those duties when he played, because he had Gattuso to win the ball (to use my previous example cuz I'm lazy), but he had to make the precise diagonal passes across the field, etc etc. Barry does have the vision, but I feel like his technique lets him down a lot in that respect - he sometimes looks like he's unable to kick a ball past 20m for some reason... I get it towards the end of the game as he's ancient, but it just seems... unnatural when he tries to make those passes lol
Then again this is my guestimation based on observation, as I'm not an actual football manager (YET HEY HO), nor am I living in Martinez' head to know the exact, specific way we've set up. For all I know we're both plebs and we're wrong.