The Crimson Binome
Hero
No, because the rule for how much damage a dagger deals is clearly stated, in ways that the rules for counterspelling (and stealth, and many others) are not. The DM in an AL game is obliged to follow the rules in the book, but where those rules are left up to interpretation, the DM still has the same freedom to interpret as they would at any other table.This allows any rule to be ignored in AL, then. That seems to go against the spirit of AL. If a DM wants to say daggers do 10d20 damage because of his interpretation, that'd be cool, right?
Fifth Edition is not written to the same degree of precision that 3E or 4E were. There are places where the DM is forced to make a judgment call, or else there's no way to move forward. This is one of those places.