You use the spell serpant ward because your dummy spell I think is based off of serpant ward. For unit issued point, you use the spell your spell is based off. But it can make leaks if you have more than one spell based off of the same skill and you use the issued point.
Ghan has said he has fixed this. Monovertex please confirm this fix. This was only a problem with people that had signatures in the upper levels like not the special members but the respected members.