  ::::OK, I dug a little deeper. From the photos and descriptions I came across, it appears that a typical wooden track uses 7 layers of wood for the rails that are essentially nailed together. Steel is used to pad the contact surfaces of each rail. Topper track takes it a step further by replacing the top two layers of wood with steel that is bolted in a tight pattern to the wood frame. Because the remaining layers are still wood, the industry continues to classify them as wooden roller coasters. As for coasters using the Iron Horse track and wood supports (what I'm calling hybrids), does it make sense to create a separate classification for these?  I understand Wikipedia is not the place to do so, but I wonder if any experts in the industry are considering doing so.   