Strolling down the halls of the offices of post-secondary instructors I think you would get many varying opinions on the importance of lifelong learning for instructors. I think it all comes down to the reason you choose to teach. If it happens to be for the summers off, perhaps lifelong learning isn’t as important to you.
I think that in order to be a true professional in the field of adult education, lifelong learning is crucial. Courses such as the PIDP that I am in right are a great step, however I think there is just as much value in almost any other type of course. I would argue that is doesn’t necessarily matter the content you are learning and keeping you mind active that is important. Have found when taking courses, other than PIDP, now as an instructor I pay very close attention to the different instructional techniques used to see if they could be valuable in a class of my own. It’s like learning two things at once!