You can't really look at wet handling laps from one source and automatically make meaningful assumptions about another. There are too many variables involved: drivers (racing driver vs mag journalist and their preferences of suspension settings), magnitude of damp/wet, track layout, stability control systems (some are more lenient than others), etc. Even between Sport Auto's and Autocar's wet handling laps, there are strange discrepancies. What we can look at is the M3's performance in this TopGear test with similar performances in the backs of our minds: the M3 CSL was very fast despite Cup tires on a wet track. The LFA was also very fast on a wet track.
These examples support Autocar's conclusion about the old M3 vs S4 dry/wet handling test: a naturally understeering AWD car can have its understeer exacerbated in wet conditions, while a RWD car can be more neutral/adjustable/pointable in wet conditions. And the normal weight, which can aid traction between tire surface and dry surface, seems to become more of a liability when those surfaces are separated by a thin layer of water and grime: the car's mass wants to pull to the outside of the turn radius.
The TopGear LFA example also points to Clarkson's minimal impact on lap times: he didn't seem impressed with that car and pretty much slagged it off as a joke at that price. Yet The Stig put in a good wet lap.