I have stopped patching and setting them aside for later because I too was seeing a high failure rate. If I patch a tube it is immediately placed inside a tire and inflated, based on the idea that the constant, even pressure from the tire "seals" the patch more effectively. I've seen much more success this way. FWIW.
So the routine:
New tube gets used on the road for quick puncture repair.
Punctured tube is patched and re-inserted into tire at some point before the next ride.
Spare, unpatched tube goes back into saddle bag for next time.
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A race bike in any era is a highly personal choice that at its "best" balances the requirements of fit, weight, handling, durability and cost tempered by the willingness to toss it and oneself down the pavement at considerable speed. ~Bandera