Working in the wet Pacific Northwest, as a Bellingham home inspector, I have often thought that substituting chains for proper downspouts was a poor idea. Honestly, I think a house with chains on the gutters would do just as well if the gutters were left open -- nothing attached. Chains are no better than nothing!
I have some pretty conclusive evidence. I was at a house with chain downspouts when the rains came. As you view this video note the extremely wet corner that is being splashed. Uncontrolled runoff water will damage building materials -- rot was apparent at siding that was being splashed on an ongoing basis. Those dark areas, face of the corner, had been wet way too many times over too many years. At this point, the house needs not only downspouts but siding repairs at some locations.
The video tells the whole story, check it out.
Moral of this story, get rid of those chains before you wreck the house!