Well you're not using it to predict, you're using it to discredit.
Why don't we just keep the context that he has 18 assists. That's the way the leagues done it for a long time.
It's the same thing. If you don't realize why it's the same thing, I would encourage you to think about it.
The "way the leagues done it" is not necessarily the "correct" way to do it and it's closed-minded to assert that it has to be.
Any goal, could be broken down by its primary, secondary and tertiary assists. You could then weight those three events an infinite number of ways. The NHL decided, completely arbitrarily and backed by zero research, that the weightings are:
primary - 1.00
secondary - 1.00
tertiary - 0.00
you could weight it any number of ways - 1/0.5/0.25; 1/1/1; 1/0/0, etc. and it would be just as valid but at the very least the actual research into this topic has shown that a secondary assist is not worth the same as a primary assist on average. Regardless, my only point with regards to this discussion is that Goldobin's production is not good and is even worse when you realize that it is propped up by an unusually high ratio of secondary:primary assists.
You don't NEED to weight his secondary assists at 0 to show that his production is bad. The point is that it's bad.
EDIT - I should have probably expanded this as the NHL (completely arbitrary) definition of points being:
Goals - 1.00
Primary - 1.00
Secondary - 1.00
Tertiary - 0.00
When it's probably more valid to weight goals more than assists and primary more than secondary, etc.