Well, with all due respect and acknowledgement of your well stated points......
Yes, ozone is everywhere ..however I've never seen UV damage on something that has been kept in the shade (UV=ozone).
All the other stuff you mention is fine and dandy ..and if your wallet is ample enough to leave a perfectly functional spare unused for over a decade, leave it in perfect shape, and discard it for whatever reason ...then far be it from me to attempt to alter your feelings in this matter.
I, however, have many OEM items on my only ancient vehicle and have no intention of spending (potentially) over $100 for a tire that, when used in the recent past, has proven to be 100% reliable.
If anyone can tell me how a spare failing on the road is any different from having your regular tire failing ...even catastrophically .in terms of safety???
Hence ALL you are left with is the inconvenience of being stranded until the road service guy can get around to you.
Again, I'd never get in the way with a man parting with his money. The anxiety of not doing it is worth the $$ spent.
As a semi-informal survey:
How many of you have had cause to use your spare in the past 10-15 years on the same vehicle??
My 1992 mini-van
Once about two years ago when my son borrowed it to go to NC. This was the OEM spare.
My next to last event was with my mother's 1986 Corsica in 1995 where I saw the low tire, and instead of getting it fixed, just added air. It ran low again and upon filling it again (going to work) it developed a bulge. It blew and I used the space saver spare until the next day.
Before that it was in 1987 on our 1986 Tempo. I hit something nasty on the road and it wouldn't hold air long. I bought a new tire.
That's 3 instances in 20 years. One from neglect ..one from road hazard ..the other unknown.
btw- is there any NTSB advice or regulation of spare tires ..in terms of a static fatigue rate? Any OEM recommendation to discard one (there may be - I've never heard of it)?? Even in something like our hopelessly anal Audi type car?
If no such authoritative information exists (it may-I've just never seen it in print
) then we are indeed debating folklore. Not bad advice, by any means, but folklore none the less.