Dom This would work fairly well:
- Use an automated video process via Hawk-Eye style technology for offside, boundary or goal-line decisions. Get that tech to the point it just works with minimal or no supervision.
- Captains are allowed to call on the VAR once per half (once more for extra time) on penalties, free kicks, red and yellow cards, and other discretionary decisions.
But I think the match referee has to rule on the second kind of VAR process and they should be miked when they do.
If an off-field VAR rules on contentious decisions, we've seen they're reluctant to change the initial decision (and the "obvious error" criterion doesn't work).
This leads to the VARs doubling down on bad decisions and degrades the match referee's accountability.
If the number of captain-initiated VAR processes per match were under 4 we'd be alright. One per half seems safer than two total, otherwise you get annoying strategic use of appeals to waste time at the ends of matches.