Quote:
Originally Posted by Flinx
It is not that this rule is not clear, I am just wondering why it exists and if I am overlooking any implications. Except for defense rolls as mentioned, this reduces the rule “3 and 4 are always a success” to “if your effective skill is 3, 4 is also a success”. And the odds for effective skills below 3 are so discouraging that it seems pointless to forbid it. If a player wanted to try something with an effective skill of e.g. 1, as a GM I would just say “You know this has only a 1.85% chance of success and a 50% chance of a critical failure, are you sure?”
But perhaps I am missing something here. Let me know if you think this is a rule that can be ignored without any impact.

The rule probably exists because it isn't physically possible to roll less than 3 on 3d6. Since it is effective skill we are talking about, it isn't unreasonable to say that you should have
no chance of success if the situation reduces your skill to less than 3. Otherwise you would be allowed the possibility of getting lucky and rolling a critical success on a 3 or 4, 2% of the time, and not only being successful but wildly successful, which doesn't quite seem fair. Even allowing a noncritical success on a roll of 3 with a 4 being a failure is a bit of a stretch, though not as bad a one. The key to remember is that a 2% chance of success is, on average, a success once every fifty tries. A success on a 3 would be bit less frequent, about once in 200 tries for rough figuring.
That said, it doesn't seem likely to break the game if you ignore the rule but you do need to determine whether success that often, under conditions that adverse, is going to break your suspension of disbelief.
The other thing to consider is that you've essentially opened the door for rolls when effective skill is reduced to 0 or a negative number. The argument can be made (and has a certain mathematical validity),that if you allow a roll for impossible results like a 1 or 2, you should also permit them for the equally impossible values of 0 and 1, for example.