I voted no. For one, to "fix" this would be a massive waste of time to get rid of something inconvenient at worse. Personally, I like having the double warnings. The warnings at ten marks lets me know whether I have to worry or not. If I need to move some vehicles or idle some structures, the five-marker is a more urgent reminder of that, and generally I put a bit more thought into ensuring the safety of vital units/structures during that period of time.
So, I guess this is my thought process.
At ten marks (assuming the danger is relevant):
-Wrap up whatever I'm doing elsewhere on the map so I can focus on the impending disaster.
-Start idling structures and moving units out of the way as applicable.
At five marks:
-At this point my full attention is on the upcoming disaster.
-Make some predictions about the size, direction and damage potential of the disaster as applicable.
-I make some last minute calculations and judgment calls. Combat units are relocated safely away and spread out so at the very least my defenses aren't crippled. Cargo Trucks and ConVecs are moved as well, though they're generally kept closer so they can get back to work as quickly as possible.
-Vehicle Factories start to produce Repair Vehicles to fix up any damage as quickly as possible.
So while it may bother some people, to me having two warnings for the same disaster is a pretty important part of my disaster management process.