I've been thinking about this long and hard, and it's really difficult to try to explain what I want to say.
Let's think of it this way, we're the DC and DL coach and the LB coach sitting together to come up with a way to generate pass rush.
We realize that's there are many ways to do things.
Somebody suggests that we have guys who can penetrate the interior gaps (Watt, Antonio, Mitchell) and we also have ILBs who have quick first step and short burst.
The shortest distance to the QB is a straight line; ie. to the inside.
If we can somehow set a guy free or going against a one-on-one match up, we have plenty of opportunity to cause have in the backfield.
On first and second down, when the run is still in play, this will also help disrupt the mesh point (if the QB hand the ball of to the RB).
By not having an OLB taking an edge rush all the time, we can also guard the outside run or reverse better.
In passing situation, it's also effective against the occasional draw play.
Another plus is that we can drop an OLB back into coverage instead of our ILB, giving the defense more variations in disguising the pass rush and coverage.
Sometimes, it can help against the screen pass if one of the OLB doesn't sell out to go all in. There's also benefit against the bootleg or roll-out.
Obviously, we can still rush both OLBs whenever we want to.
But with the personnel we had inside, it might be the more effective way to go about it.
I don't know how much sense that makes, just my thinking is all.