Your post looks interesting and might well be 100% correct but I don't know - nor do I know anyone who knows - what the various little pronunciation guides or whatever they're called mean. It's why people tend to say "car as in carpet".
No, "car as in character" is still. Car as in carpet, char as in chart - simple and doesn't require a course in IPA, which may I remind you precisely nobody understands.
I don't know what happened to my post but i meant "car as in character is stupid/ambiguous". But it's perfectly possible to understand "car as in carpet" and it's generally possible to find a similar pronunciation of a sound.
"Plenty of people" is misleading. Plenty as in thousands, millions of people worldwide, possibly, not not plenty as a percentage of the english people world. I'd be surprised if more than 5% of english speakers look at an IPA description of a sound and do anything other than go "what the fuck does that mean?".