>Please cite the governing title of the CFR (Title 49 section 236 subpart B - "Automatic Block Signal Systems") which prohibits either of these; or any other authorities which will substantiate these assertions.

Took a look, and you're correct there is nothing, at least I couldn't find it in after thumbing through it. It is odd that the CFR uses the term "home signal" but then fails to define it (nor had the GCOR for several decades for that matter). My assertion was based on discussions in meetings with the FRA. What the Frisco had done was take some dark territory and install CTC by adding power switches and controlled signals to the ends of the sidings and then add just one distant signal approaching each control point [on the single track]. A train had been flagged out of one control point and took off after passing the yellow distant signal approaching the next control point, failing to realize that it wasn't a home signal nor that there could be a train beyond it, which there was, with a rather serious rear-ender resulting.

If professional railroaders can't tell the difference between home and distant signals, what are the chances "museum railroaders" can? As for those AC line relays, how about the interference problems BARTD and WAMTA have been having?