If by shelf life you mean that sometimes TC corrupts, yes, that has happened to me twice...
No matter.. wipe the TC drive and let er rip.
I find this to be an invaluable tool.
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"If it turns out that President Barack Obama can make a deal with the most intransigent, hard-line, unreasonable, totalitarian mullahs in the world but not with Republicans? Maybe he’s not the problem."