Well.....Capt. Laidlersays otherwise, he has written several times that in terms of absolute accuracy the front loaded No4 rifle did better than the center bedded. I seem to recall that Major Reynolds in his 1960 book on the Enfield says the same thing. Major Reynolds was involved with the entire adoption of the No4, so you have two first hand sources saying the same thing.
Given that the sniper rifles were hand tuned, if the center bedded method was better I suspect the UKwould have gone to it. Still for competitive shooting with a sling the center bedded method seems to work about as well as any method.