I agree about the additional weight, and energy stealing bounce... Mine robbed power especially when climbing hills (due a bit to the weight, but mostly to the pogo stick action).
When I switched to a suspension corrected rigid fork, I noticed better climbing as I expected. However, what surprised me was the handling felt more crisp and precise as well. As I thought about it, it made sense, because of no fork compression while turning.
My suggestion is for road, path and rail trail use, a rider should avoid suspension. However, if you desire suspension, the bottom line is do whatever keeps you riding. If one opts for suspension, I suggest springing (pun intended) for a fork with a lockout in order to gain some of the benefits of a rigid fork when you lock it out.
Even with paths in poor condition, I prefer a good quality wider tire, and lower pressure (if your weight allows) to help to reduce the bone jarring impact of the rough surface.
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Slow Ride Cyclists of NEPA
People do not seem to realize that their opinion of the world is also a confession of character.
- Ralph Waldo Emerson