Bella Carroli (sp) a gymnastic coach never did gymnastics, but has trained gymnastic champions. Same goes for many other things. Some teachers can fight and can't teach.
Yes I would take lessons from a teacher who never have to use his or her skills in a real fight because the highest form in Martial Arts is never have to fight. As long as the teacher has a vast knowledge of self-defense applications that are effective and able to teach it to students right.
Taiji Quan for Self Defense