zoomers

I am currently reading Phillip Whitten's "The Complete Book of Swimming". He talks a little bit about using fins in the section about training and says that they tend to become addictive, so he likes to limit fin use to 2-3 times per week, 1000 yards maximum per time. I definitely agree that they can be addictive (fun, fun), but would there be any sort of disadvantage to using them for a whole (or half) workout, say once every two weeks? Should I limit use to 1000 yards a practice because I could hurt myself otherwise? I'm interested to know how (and how often) other people incorporate zoomers into their workout...