After I had taken the layout back to bare boards I grabbed the Trackrite underlay foam I had picked up at Liverpool and did a bit of a test to compare sound. I used a few Trainorama FWH's as a 'control' wagon for this test to produce a consistent result - nothing better than mass-produced wheat wagons for conformity! The first one was track on baseboard, the second was laid on Trackrite, the third was track on Trackrite with another layer of Trackrite under that to try to replicate a similar effect to Gary Spencer-Salt's efforts on Spicer's Creek. (Though recognising that it isn't the same because his isolates the underlay from the scenery foam and then has trackrite on top). To me, the second one (baseboard + Trackrite + track) sounds the best.
For now I've decided to use the larger roll of Trackrite foam to wrap the timber baseboard to achieve the same 'isolation' as Gary has, but I'm not sure yet whether I'll then lay individual pieces of Trackrite on top of that layer or just put the track down onto it. Whichever way I go would require this first step, so today saw the first break from procrastination for a long time.
I positioned the foam roll on top of the baseboard with around a 30mm overhang on the far side to ensure I'd have enough to attach to the sides once folded over. I then cut the closest side to the same dimensions.
After I'd spread Selleys No More Gaps coloured caulk, I lay the foam as per Gary's instructions here. I didn't have enough tacks, so I improvised slightly. Well, almost entirely improvised.
Got the muse back, so I hope to have this phase completed shortly.