Re: PDF has its uses I suppose
> Trying to unscrew a welded joint is also tricky and for the same reason: they're both intended to be unchangeable.
Nope. Again that is one of the many and most commons misconceptions about PDF.
The output was not designed to be changeable. That is an altogether different kettle of fish than "intended to be unchangeable". You are mistaking a non-goal by a requirement.