This sounds exactly as awful as everybody with a bit of sense has predicted.
I'd rather we get the odd incorrect offside decision than having to wait 3 minutes for a correct one.
Think that's incredibly harsh based on one game. It sounds like by the second goal they'd already got more used to it. The international between Spain and France had no such issues.
It's not about the odd incorrect offside decision. It (for me) is about taking power away from the clubs that enjoy referee bias more often than those that don't. You only have to look as long ago as what 20-30 mins since the last incident of this nature. Man United get a penalty that wasn't a penalty against a bottom half team. How many times have we seen such things? It's been a constant in my time growing up with football. It's a simple fact that it's the least path of resistance for a referee to give a marginal decision in favour of the big team than not, and they do it in abundance. It's probably not a conscious choice, but if they give a decision that allows a top 4/6 team to score when it shouldn't have been...what happens? Nothing bar playing back of a few replays at HT, maybe a question at the end of the game? However, if they make a decision that goes against the big team, they give a penalty or an offside goal to the smaller team and they go on to win...and then what? They have endless discussions, phone ins lambasting them, pundits calling them out in columns, pressure to drop them for the next PL game, etc, etc.
If Man United win today 1-0 from that bad call, it will just be a footnote in the match report. Maybe pundits say it was a "soft" penalty, or that "there was contact" as if touching another player was reason enough. They get the 3 pts and everyone moves on.
It's one of the biggest imbalances in the game, and personally I'm so done with it. For that reason alone, it's worth it to see if they can have a fairly seamless 4th official. It's worth a long enough experiment.
They could've made the right decision there before Rooney even walked up to take it.