Tire retreads, danger or valuable resource?

All of us probably drive down the expressway and see the fragments of blown tires littering the road. This highlights two points. One, all of tires need to be replaced is obvious, and are those retreaded tires that blew? If retreaded tires are blowing more often than non retreaded tires, should we keep using them? If we do, we will save huge amounts of oil by retreading as opposed to replacing worn tires. There is much written already about the safety of retreaded tires, and the NHTSA has guidelines which must be followed. It seems that if the guidelines are followed, the retreads are safe. If they are safe, we should be using them, for sure.

[Source: Treehugger and NHTSA]