Its football. Pretty simple stuff.

Yes, 1st up. Run blocking vs pass protection. in run blocking-
A man up scheme or zone blocking.
Double teaming, back side seals. 2nd level assignments - seal a specific lber or safety. Reach blocking, the assignment is not the guy in front of you. Its the guy in front of the guy next to you. Blitz and stunt assignments. It used to be the qb would call out any adjustment at the los. Now its more often the center. They'll make the line call in the huddle by the playcall. It built into the play. If the D expected is what is seen pre snap. There is no line call adjust. Often theyll still call out a bluff adjust.

Both zone & man blocking schemes have a level of pulling linemen. Zone schemes have much more. Then theres trap blocking. At the snap, you block the player opposite . So if your running right, normally you would try and ride the defender left. Trap blocking. You begin riding him right, but do so half assed, let him get by you. As he gets by, the lineman pivots and blocks down its usually done to open a specific gap. The greatest trap play invented was the famous parcells " counter trey. An inside run where the center & guards block in specific directions. Then pivot. The 3 guys inside now use the defenders intsinct slide him by vacating the designed gap to exploit. Pivot and then seal that defender from behind him. It really screws with the interior defense line through out a full game. Not nowing whats a trap and whats a straight forward run block. Its especially effective against quick defenders. Lesser so vs 2 gap dt's like jerry ball/ pat williams that are schemed to just clog an area. Its the run game version of a screen pass. Let the defender use his aggressiveness and 1st step to take himself out of the play.

In pass protection. Its still not rocket science. But the pass protector is at a disadvantage from the moment the ball is snapped. The biggest thing used to be. Maintaing gaps and creating a predetermind spot that will be the center of the pocket. The line has to use the devenders momentum and guide him marginally left or right. Using the defenders own energy. Maintain your center of gravity and arm extension/ hand punch. Maintaing moving interference on his routein doing so to create the defenders center of gravity to alter his balance as a weapon to guide him to your designated defense zone of the pocket. With the rise of mobile qbs, the pocket is less often where the qb recieves the "hike". Escape lanes become the design instead of a tight ( gapless) pocket as it once was.
The biggest issue in this era is blitzing & stunts, delayed blitzes that are the defensive version of the trap play discussed above. Deception and a counter move. The goal is always the same. The only variances are how o-schemes account for keeping the qb upright long enough. In a base set. It 5 blocking 3 or 4. Zone schemes. Its not always the man in front if you your trying to prevent pressure its the area in front of you. In man schemes it is the guy you are closest to and if he stunts. You circle over & block him. Or, if its the play design. It might be a slide by 2 o linemen anticipated in the weeks practice bc the opponent stunts alot.

The problem with the vikings zone scheme. Zone blocking became en vogue 30 years ago. An era where defenses emphasized big & strong. Not so much pute speed and lateral agility like the modern front 7. The speed most defenses have up front. The lateral quickness? Those gaps that a zone scgeme looks to open become backside tfl lanes for the 4.4 lber. The vikings zone schemes also require a bunch of reach blocking and 2nd level assignments as the primary target an 0-lineman might have. The space the guard or center vacates in these situations becomes a straight shot, unabated for a tfl or sack. As well in zone pass. Ive witnessed a center or guard defending his zone and 1 o-lineman is suddenly trying to block 2 defenders.
Youll hear an announcer say, " soneone missed an assignment". Well. Tecnically yes. In reality. The defender with nobody in front of him has the direct path through that hole. The reach block assignment to cover that gap is further away. By design. That line call is dependant on the defender hesitating and being too slow to get through & blow up the play. Hey. That worked in the 90's. Not so much in this era. If youre running a zone scheme. Those d frontbguys have been studying film all week & identifying those moments where gaps will be momentarily vacated. Where an overload to one side will confuse the free guard/ center and lead to 1 olineman trying to block 2 and not hindering either.

An era defines the schemes a coach should be using. Well. In my opinion anyway.

Pay attention to how vrabel runs the ball in ne.
Theres much trapping and misdirection. In minnesota? Bradburry was asked to pull on nearly every play. In ne. He is a leverage/ trap blocker. At least as often as hes pulling, reaching or 2nd level on a lber combined.

It'll be interesting tho. Seattles front 4 is large. They ask the dt's to 2 gap and muddy the middle a lot.

Man I wish we had Vrabel! He was a bad arse lber through both era's. He knows how to defend both schemes. Zone blocking/ man blocking. Imo, its telling as to the trend. That he's running his rush offense with more elements of the parcell scheme than the Kubiak zone scheme. Wait until he gets his larry csonka drafted. He's gonna own these defenses largely built on speed over strength at poa.