My argument is that the fickle nature of RL fans means that, when relegation is present, they quickly desert their club and pick and choose fixtures. A club like Hull may get a one-off spike of 5400 for a deciding game against Sheffield (1999). But when you look at the whole season the club had sunk to the depths of 3100 (Salford), 3800 (London), 3500 (Leeds), 3600 (Wakefield), 3400 (Halifax), 3300 (Gateshead) - because the bulk of the fans had walked away in despair. In some cases the spike is relative only to how low any club has sunk.
Whether P&R was present or not, the crowds would have sunk that low. The fact there is a spike is a bonus against the non-jeopardy games.
The presence of relegation, as you're suggesting, is not the reason people abandon a club. Lack of success is. That jeopardy brings people's interest back temporarily... something that didn't happen when there was no P&R. There were no wooden spoon battles.
Wakefield are down to 3,600 for their last game with Warrington. If they end up having a relegation decider in September they may get 5,000 - hardly a time to celebrate if they have 5 more 3k crowds during the rest of the season because fickle fans have gone AWOL (due to grim reaper thoughts about going down).
If you really think fans have abandoned Wakefield due to the threat of relegation and not due to selling off the majority of their best players in the off-season due to financial issues and having their ground capacity significantly reduced on top of further off-field disappointments (such as the new stadium not happening and significantly less investment), then again you're ignoring things to push your agenda. This would likely have happened if there was no P&R.
By nature we are a bunch of miserable doom mongers. Look at Salford 6900 to 2900 in 3 months. Add relegation fixtures into the mix and we sit at home moaning at the radio with our prosaic fearing the worst. When there is a chink of light we might or might not turn up for a one-off game.
Again, I doubt the drop off in attendance at Salford has anything to do with the presence if relegation. They're pretty safe. It's the lack of success.
Bring relegation in - I am comfortable with that.
I'm not sure you are, given that you're arguing fans are deserting their clubs due to a fear of it!
But the RFL suggesting fans of Bradford, Wakefield, London etc. are rubbing their hands at the thought off a battle against relegation (and some jeopardy games) is extremely short-sighted and goes against how fans have treated the sport.
There are no jeopardy games this year. Off-field issues have superseded on-field battles. You can keep saying there is a relegation battle, but there really really isn't.
When we start a season with clubs not having major financial melt downs and points deductions imposed on them, then maybe that would be a good time to throw around the jeopardy argument.