Desmond Howard says we might defend against Duggan runs with a "mosh rush"

Not correct my friend. The girl and guy in the bakground are doing what is called a two step. Most likely to a groove based section of a hardcore song. A breakdown and hardcore dancing is likely to follow in short order.

The kids without enough rhythm for a good two step are planning out their spin kicks and crab punches. 
 

Guy that enters from the right for just a moment with a hand bandage does however look to be doing a more skank based two step. 

Skanking, I'll have you know, comes from reggae. I was taught how to skank in 1974 in Kingston. I've always thought it entered Britain and the U.S. via the ska/two tone movement, with bands like The Specials, who also played punk. 

And--I suspect a lot of people know--a mosh pit was the place in front of the stage where people danced like fucking hell and you knew if you joined in you had to give it your all, in punk music starting ca. 1975. East Quad. Big fun. 

Hell of a way to get to the front too.  In my younger days I'd seek mosh pits out from the back of the floor area.  Stand at the back of the pit for a few minites, wait until everyone inevitably got tired and then sprint across.  Depending on the size of the pit you can make 20 or 30 rows of people up sometimes.  Depending on the size of the venue you can find yourself 10 rows from the gate in 2-4 pits.

I resemble that remark.  

Was always more of the arms folded head nodding type who watched the band play on the floor a few feet away

Definitely . On the edge was fun for me. Can watch the pit. People will run into you and you can push them back into it. Fun way to be involved without taking an elbow to the face.

As long as you can pay attention to the crowd killers. I don’t know how big that is anymore but you used to have to keep a look out. 

I'm no Xs & Os expert, but I imagine you could keep contain with the DL (& LBs?) and still manage a few blitzes from the secondary (& LBs?)

I'd think the idea would be to avoid somebody like Okie flying in and losing contain in pursuit of glory.

Edit: typos

You still try to advance on the QB, you just don't sprint. Imagine moving forward while in something like a basketball defending stance. It's a lot slower than running at him, but it it keeps him contained and it does lead to pressure eventually. 

No, because after a few seconds either O linemen or D linemen start to bump into him and he has to get rid of the ball and can't scramble.  At least that's the point of the mush rush:

1. Make the QB get rid of it early and short-ish (require lots of positive plays in order to score)

2. Make the QB inaccurate if he gets rid of it late because of the proximity to bodies (generate interceptions)

3. Don't allow the QB to scramble late in the play (minimize broken play miracles)

So, if they're achieving those three things, I would agree with Desmond, that is a great way to contain TCU's offense.

They also get coached to keep the hands up on this type of rush as you'll get a lot more deflections than usual given that the interior DL often ends up in "no man's land" between where they'd  generally push the pocket and the LB's. 

LB's will probably play a yard or 2 further back as well.  Dangerman becomes the TE and slots getting a bit further downfield than usual, and giving up 3-5 yard runs on what would be 1-3 yard runs.

My favorite element is the combination of a dreadful pass and Schoon waiting on the throw.  The play so baffled OSU that Schoon was 10+ yards open so Mullings could just toss in the general direction. It sent the messaging of toying with Knowles’ defense and put a little more swagger into the offense.  They knew OSU was toast.