Does it seem evident and logical to assume that the reason for sticky shutters i s the use of old technology lubricants? Maybe it would be much better to use the new and modern high tech lubes like TEFLON. There is a product called SUPERLUBE that contains teflon. Would this be a safe alternative? Why do some shutters st ick at low speeds and others do not? Is the cause an adjustment or a lubricant p roblem?