It would be interesting to know how many guys here had ever had a blowout in their Camaros. I bet not many others run old tires like we do. These rides have been nice for a long time and we tend to hang on to what still looks good such as tires.
While I respect Royce as an authority since he works in the trade I have a hard time believing these are time bombs. It just doesn't sound right.
It's up to the owner to do what's right for them. As I stated before the tire is not going to suddenly burst into flames when it gets old. If all you do is cruise around town then you will probably be fine with 20 year old tires that "look" like new. If you get out on the highway and build some heat in the tire, all bets are off. It's your car and your family riding in it, personally no way I would run a tire over 8-10 years old period, I don't care how good it looks.
Part of my job is failed tire analysis, looking at what use to be a tire and figuring out why it failed. There are many many reasons why tires fail, some of the tires look like brand new. As I said before there is a lot more to a tire than people realize. I was guilty before as well, once I got into the industry I learned a LOT.
Once again the use of the tire has a huge factor in what you can get away with. If it's a farm truck that never goes over 35mph on the road and spends most of it's time on the farm, run the tires until they rot off, no real risk there. If it's your pride and joy that will see higher speeds or prolonged highway trips, don't risk it.
Look at it this way, how many tire parts do you see laying on country, county, city roads? Not many if any, go out on the highway and how many tire parts do you see laying on and around the highway? Why do you think this is? How many cars and trucks do you see pulled over with flats on the highway? How many on city streets, country roads? There is a reason and it has little to do with debris.
Only you know how your car will be used, do what's right for you.