How do NFL scoring rules "stack"?

Our scoring rules come directly from the official NFL stats. Here's how they're scored:

• A tackle for loss (TFL) counts as a tackle.
• A sack is a TFL, so any TFL will trigger a sack rule with just one exception: a sack for no loss (i.e., a sack at the line of scrimmage) will not be counted as a TFL.

If you want to award points for TFLs minus sacks, you would need to create a rule just for sacks that will undo the effect of the TFL rule. For example:

2 points for every TFL-2 points for every sack