Using glue to hold ballast on 1:1 tracks is nothing new. Back in 2005 when I visited Japan, when I was waiting on the platform of a Shinkansen (bullet train) I noticed that the ballast on the tracks was sealed with some sort of adhesive. It even had a satin sheen like when you apply too much white glue to N scale ballast. They do that so when a train goes by the station at high speed the ballast isn't kicked up onto the platform and passengers waiting there.