nearly three yrs ago I wired in an electronic dimmer switch to one of the transformers that feeds 12 lamps on a portion of my yard. The kind that has variable ramp rates. I adjusted it to the slowest setting. Soft on and soft off. This spring the lamps will be 3 yrs old and not one has been replaced yet. They are all operating between 11.5 and 12V. 12 lamps is hardly a test. Has anyone tested this on a larger scale and have you found this to be an effective way to extend lamp life?