Thank you, I can see that! I think that it reverted to 4 track after the war on the basis that the arrangement in the map would have been photographed and remarked upon if it survived to, say, the late 50's.
As a general question, is there any difference between gauntleted track and interlaced track? Usually, if there are two different railway technical terms they cover slightly different situations - unless the GW is involved...
The LNWR seemed to warm to interlacing/gauntleting; I think that when the Euston - Roade section was being widened at first only a single slow line was built with single track tunnel bores but, when the slow was subsequently doubled, interlaced track was used through one of the tunnels. Must have been tight! There was a particularly destructive crash when a train went through traps into the retaining wall to the side of the tunnel mouth, I think. The advantage of interlacing in that case (like Selby) is it obviates the need for point rodding to the remote p&c if the tracks converge/diverge. The LNW also seemed to use it during underbridge/viaduct/tunnel works to give more room on a normally double track line.