DCC works great for my layout as is, and this question doesn't even apply, unless... I've given previous consideration to the idea of expanding my layout into one or two new sections. More accurately, one or two entirely new layouts, with just enough interconnecting track to really make things interesting! The challenge is that there is no way I could run three layouts from my current operator's spot. I'd love to do three independant layouts, with three independent DCC systems. I'm just wondering about one of the technical issues involved. I thought of two, strictly DC, layed in series with eachother to provide isolation for two sets of DCC equipment? The question though, is whether a locomotive that runs from a DCC area of track into a DC area of track would understand that it needs to keep running? *edit* if this works, it could really change the way club layouts and modules are set up, as one operator could run a set of yards with switching, while more operators could run the mainlines.