I have no 'empirical evidence' but it seems fairly obvious that what works on one vehicle (an old fashioned, lardy, RWD live axle car) may not work on another (FWD, all independent suspension, lighter) so any
universal rule is stretching it a little - people's experience may vary and anyone doing this needs to try it a step at a time for safety.
I did this in 5psi steps since the spring and now I've settled on pressures of 45 (makers rating is 36) which seems like a reasonable compromise - sidewall max is 51 fronts, 54 rears. This has made coasts much better and dry handling is improved. Wet handling is no different but when I tried 50 it did get 'lighter' at the rear, 55 and it was very edgy on roundabouts. Ride quality is always bad so it made no difference.
I did the same on Mrs A's Octavia (also 35ish makers rating) and took them to 40. All OK, tried 45 but the handling certainly felt worse and ride was far more crashy - too bad for Mrs A. I backed it to around 42 and use that now and she has reported better tank to tank MPGs depending on the trips she is doing.
Most roads here are black tarmac and they do get quite a dousing of fuel spills and drips especially from commercial vehicles such as trucks and buses. The first bit of wet weather just after a spell of dry is always dicey. So its worth knowing what difference any changes will make.
Disclaimer - I am not a racing driver or extra special trained and rarely track day. I have driven skinny tyred cars since 1985, and I did get Driver of The Day at Knockhill on my birthday a couple of years ago - in streaming wet weather and on slicks too.
