Weighted links - co-linear points

Hi,

Why can't we have co-linear points on the independent side of a weighted link?

It's easy to get the warning message

'The independent geometric entities must not form co-linear points'

by selecting any 2 points for the dependent side (must form a straight line),

This is CREO2.0 M030 (I don't have any other versions with me to check)

Thanks

Thanks