I think the feature got more confusing as Apple started to phase it out. They dropped the feature where you could force-touch to select text (on e.g. a web page rather than typing) and press harder again to select eg sentences/paragraphs. They also made force touch and long press do the same thing in many cases. I think about the only place it works well is in the keyboard but sadly there are now a bunch of bugs there with replacements/corrections not interacting with the text suggestions properly (and they deleted the feature where pressing shift while replacing will capitalise/uppercase the suggested replacement)