I recall reading the lengthy thread at the Casita forum, at the time it was bashing Goodyear Marathon trailer tires. It has been a good year since I last checked so I am not up to date on the latest. I am however concerned about tires and the unpredictable failures. Thane had three factors contributing to the failure.
The first was probably the high temperatures, not much you can do about that. However if you are likely to encounter those conditions or have encountered them I would contend your tire life is shortened. A second factor was drive time, five hours will build up even more heat, and again I am not sure what you can do about that. Third is the age of your tires, without looking at the "born on date", conveniently
located on the inside side wall and frequently in code we can only guess as to age. We do know at least four years of age.
You never know how long a tire sat on a distributor’s shelf. Nor do you know if proper stock rotation was carried out on inventory. Check your spare Thane, if it was from the same batch you may get a “born on date”. It would be best to have the date for the failed tire, if possible.
I think four years is the maximum you can expect out of these tires and I have always replaced all tires around such a date. The four years is subject to a lot of variables, one is heat. If you drive at highway speed in 90 degree plus temperatures for numerous days I contend you need to take a year off tire life.
Another factor I have an opinion about, but no proof, is storage. Tires subject to sunlight are going to deteriorate faster and I am of the opinion that tires stored on cold garage floors in freezing climates are going to throw tread sooner.
It is common to hear that failed tires are showing no cracks and still have good tread. Unfortunately those are the least reliable methods of judging tire life. I am not sure brands make much difference, more important is the need to change our thinking about tires, we cannot apply what we know about our motor vehicle to trailer tires.