Jimmy Flynn is the Special Teams and Wide Receivers Coach at St. Xavier University in Chicago.  Coach Flynn uses shield punt protection exclusively.  

The shield punt is 7 players on the line with two yard splits.  3 blockers 7 and a half yards deep, and the punter 14 and a half yards deep.  St. Xavier uses man protection,

You can see the entire hour long detailed presentation on everything you need to install a shield punt scheme at Glazier Drive.  This video is Coach Flynn's theory behind using the shield punt.

Why Install The Shield Punt?

1. The snapper does not have to block.  He can focus on the snap and then cover downfield immediately.
   
   
2. You have 7 players in coverage pursuit instead of 2
   
   
3. The shield cleans up the missed blocks.  Angles are more important than speed.  You don't want to miss blocks, but if you do, you have still created poor angles for the rushers.
   
   
4. You will have multiple players on your roster who can play the shield positions.
   
   
5. Easier Protections.  Simpler Technique.  No kick slide.  You can put your more athletic players on the front line for coverage.  The postions are interchangeable.
   
   
6. You can rugby and traditional punt from the same protection.

Theory behind the Shield Punt

1. It is a numbers game.  Nine blockers vs. ten rushers.  The snapper is removed from the protection.  The interior splits are two yards.  That invalidates the edge rusher because he is too far away.  
   
   
2. 7 guys in pursuit is better than 2 with gunners in the pro-style punt.  You don't need 10 in pursuit.  If he needs more than 7 players to cover the punt, he will directionally punt, or not punt and run a play on fourth down. 
   
   
3. It offers the safest protection and most coverage of all punt schemes.  You have an extra wall of support with the shield.  You have directional punting options.  
   
   
4. If you don't want free rushers to the 3 shield protectors, change the launch point and rugby punt.