Is poisoning a mule skill here or is it worth having on a main character? I.E. is there a benefit to having a weapon skill AND poisoning vs just having an mule poison the weapons?
The main benefit to having poisoning on a warrior template is the ability to re-apply poison to a weapon on demand, which is especially useful in pvp situations. The poisoning skill will also influence the level of poison you can inflict via the poison spell. The closer you are to your opponent when targeting poison, the better your chance is to inflict a high level poison onto them.