If it's not an option to pull over to a safer location to try to patch the tire, then that would hold true for jacking the car up. Think about it, you're at the side of the road, flat tire, etc. You think, too dangerous to patch this tire here. But it's safe enough to jack the car up?!?
If you have a flat, you can always creep the car along further to a safer place. I've never ever had a tire leak that was so catastrophic that I couldn't at least limp it, nor many millions of drivers. Most nail punctures are such slow leaks, people notice that they have to put air in once a month. Most screw punctures, you can top up pressure, drive a bit, and repeat indefinitely. Even a large irregular puncture, which are the worst, which ihawk had, and she could still limp it along.
The only time it would be that catastrophic as to force you to stop in a location so dangerous you shouldn't try to patch/jack, let's say a blow out on a highway in an urban setting with narrow shoulders with concrete barriers at the side so you can't just pull off into the grass like you can in more rural settings. If you're gonna say it's too dangerous to work on the car at the side of the road, compared to jacking up the car? It just doesn't make sense . . . have you used one of those patch kits before?
I've used them twice now. Both time never taking the wheel off the car. And they both held for tens of thousands of kms until they wore down to the depth markers without issue. And to be honest, I probably patched each hole faster than I could have loosened each lug nut, jack up the car, remove the wheel, and reverse it all.
Anyways, what I'm trying to say is, if I thought it was too dangerous to patch a tire where I was stopped, I wouldn't jack up the car either. What I want to clarify from you is would you actually stop and jack up the car if you thought it was too dangerous to patch it on the car in the same location?
I'm not against being prepared . . . I keep multiple sets of nitrile gloves, a small tool set mostly comprised of a quality multi-tool, hand cleaner, plastic bags, duct tape, electrical tape, zip ties, road flares, in the trunk. Can't even tell because it's mostly tucked between the rear firewall and the drainage for the convertible top. And in the car, I always keep a few energy bars in the glove box, and a few bottles of water behind each seat for emergencies that I cycle through every couple months (wanna keep them relatively fresh).
These days, there really is no point in keeping a spare, or a jack in the car anymore for the large majority of car owners, and manufacturers are shoving it down our throats whether we like it or not. Maybe if I were going on a long road trip or something sure . . . let's be over prepared, bring a jack. But for day to day urban driving, under 20km each way, which is the large majority of us, a jack is just over kill.
