Even easier, for a markdown (text) file, you could just tell someone the line to go to.
If people used markdown instead, then everyone would have nice text editors installed which would make this easy.
Not to mention how much faster searching through a text file is compared to a word doc (eg, you could ctrl+f the headings name and have a result instantly).
If stuff like this was adopted, integrations could be very nice (with easier solutions than saying "go to x page and look for x header", I could even imagine links being a thing assuming this feature is developed).