I watched this for the first time on a plan ride yesterday. During the session it was stated there is a technique that can replace reachabilty:
"There is one case we've seen with developers which does make sense which is if you're going to have the user answer a lot ofinformation in a form, you may not want to waste the user's time if you have good reason to believe that may later fail.
If that is the use case you care about, stay after the break because we have a new way to do that that's much better."
(Ref asciiwwdc 2018 sessions 714)
Of course there are no notes from the break. Does anyone have a reference to this technique?