Fine.
We're doing this, I guess.
My take:
In this day and age of scheming/fluidity, positional status does not matter except for the players themselves bc of pay rate.
If you have an OL that comes in lined up as a TE, is he an extra OL or a TE? He's legally able to run routes like a TE, but strictly speaking, his role is to block like an OL would. So what is he? If you ask me, he's a potential mismatch! But really, regardless of lining up like a TE, he's an OL.
Or take Duke Johnson, James White. They're RB's that catch the ball. They often run routes out of the slot. So are they WR's? No, they're just versatile and potential mismatches.
Players used to stay at their position and do only that role. That doesn't happen very anymore. Players have multiple roles. Hence, you have guys playing box safety and ILB. But are they playing like a traditional Mike, Sam, or Will? No. It's just where they've lined up that predicates what people call the position. So even if they have a similar role as to what they did before, their position changes based on alignment? That seems silly to me. You can have a play where you line up David Bakhtiari where a WR goes, but that doesn't make him a WR.
Anyways, positional status really doesn't matter. Coaches on both sides are just trying to find mismatches, whether that be lining a RB in the slot, and a safety at LB to do that, or putting an extra OL at TE. It's just mismatches. Positional status doesn't matter. BB doesn't care about positions. Just put guys where they win, and where they can make mismatches.