Tom Mangan has a good post about fixing dangling modifiers.
Writers get it wrong as often as they get it right. I think a sharp rap on the knuckles with a pica pole would properly discourage writers from backassward sentence structure, but they would avenge the affront by filing their stories later and longer. Don't need that. Besides, if writers got everything right I'd be wandering a street in San Francsico with a "please help" sign written in crayon.