I'm OK with the one ref but we need to be mindful that some of the previous rule changes over the period of 2 refs need to be thought through now - particularly on how it will bring the fatigue factor into refereeing consistency.
For example, the ability for a quick tap restart for a dead in goal now puts significant strain on the one referee to be in position to allow that to happen consistently - it might be OK at the start of a game but the pressure on a ref operating at the 79th minute or during golden point extra time to be in position to allow the same consistency of opportunity is going to be affected by his level of fatigue, which will ultimately have an impact of advantaging or disadvantaging a team over the course of a match.
If you couple this with the 6 again rule being applied, this will also potentially increase the fatigue factor for extended periods of effort on effort for referees as well as oppositions, where there isn't a break in play. Whilst players in these circumstances may get a chance for a breather once they have possession of the ball, one ref isn't going to get the luxury of having a breather whilst play is still progressing.
This is not about referee fitness - they are already at a fairly elite level to do the role now. It's about the demands of the game flow that has evolved to have 2 on the field to cover for each other on occasion...that is no longer available when 1 ref is out on the field for the duration.
They may need to revisit how some of the modern rule interpretations and structures are designed to speed the game up and, in particular, how they now impact on the practical ability of one referee to be able to physically maintain their performance CONSISTENTLY throughout the game.
What do others think?