ALTHAM - The question was hypothetical, designed to ruin Jim O'Brien's day.

Where would your team be without the 3-point shot rule?

''We'd be in big trouble,'' the Celtics coach said yesterday. ''But there's a corollary to that. If they had taken away the 3-point shot, we would have built a different team.''

It doesn't appear the 3-point shot is going away any time soon, although several purists think it a blight. And as long as it's there, O'Brien's boys will fire away with virtual impunity.