How do you propose a patch "blows off" while inside a tyre? The likelihood of instantaneous deflation (front tyre - sufficient to cause a crash) with that cause is very low: certainly compared to the more likely snakebite puncture (which I've experienced - though don't remember much after an instantaneous expletive - 2 days in ICU).
When I was a London commuter on a Raleigh racing bike, I'd get punctures every week which manifested themselves by making the bike harder to handle as the tyre slowly deflated. I had some pretty quick deflations but I never had a proper blowout. Some of my inner tubes were more patch than original rubber. In dry weather in daylight, I'd do a roadside repair and in wet weather or the dark, I swap out the inner tube and repair the damaged one when I got to work (I'm a glue and patch person and I actually collect old repair kit boxes and I'll post some pictures up later). The repaired tube would then become my spare.
Typical causes of punctures were sharp objects such as glass or slate shards and thorns with the tube damage being limited to a pin prick sized hole.
I always kept the tyres inflated rock hard to mitigate the risk of pinching the tyres on pot holes or kerbs.
All that said, every time I do a downhill stretch at speed, I have it in the back of my head that if I had a proper blow out, I'd be going home in an ambulance.
I always check my tyres before I go out on my bike. A quick spin of each wheel and a visual check for tyre damage or bulging, a quick pinch between thumb and forefinger to roughly check pressure. I rarely check the same things on my car.