Offside at 55 - defense fires off the ball much quicker. Run game for CPU and User becomes much more difficult.
False Start at 55 - creates false starts, lol. It appears to be one of the few that doesn't impact gameplay but actually increases penalties.
Holding at 55 - causes offense to hold blocks longer.
Defensive Holding at 55 - causes DB coverage to be much less aggressive and overall worse.
DPI at 55 - causes DBs to be much more aggressive. Tighter coverage, more picks but also more blown coverages.
Facemask at 55 - haven't seen much impact with this one. Get 1-2 penalties a game.
Block in the back at 55 - also not much impact in gameplay. 3-4 penalties a game.
Roughing the passer at 55 - Qb holds the ball way too long and will take multiple "coverage" sacks.
On default AP I've been running with all penalties at 55 except Offside, Defensive Holding, DPI, and Roughing the Passer. I've had really good results. If the run game is too easy, crank up Offside. If the pass game is too easy crank up DPI but do not change D Holding. I'd be interested to see what others are noticing with penalties.

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