Yeah, sure. In an Absolute Permissive Block system you could have the second train run the intermediate block permissive red (not the head block) and stop in sight of the first train.Sure it is. Most mainline signals are permissive, which definitely makes it within the realm of possibility that two trains could simultaneously be in the same block.
The permissive concept is intended to keep trains moving. Blocks signals are not anything like highway traffic signals and don't tell an engineer when to stop and when to go, the lone exception being an absolute signal displaying a stop aspect (which cannot be passed).
The gains from 2 trains sectioning a siding to siding to block is immaterial on our railroads since our runs are short and bydirectional running of track is going to require you to have traffic flow change direction on a regular basis. IE if your direction changes then the number of trains you will see between the headblocks is probably going to be one train a high percentage of the time. Our mainlines are measured in hundreds of feet not miles between headblocks. So our ability and time requirement to change direction is faster and the cycle time to process a train through a block is less relevent. These two items make the need for sectioning pointless on live steam tracks.
And lets not forget the prototype. I'll venture that permissive reds (usually plate on mast indicated) are only in places where uphill grades might stall out the trains, so we have to keep them rolling if possible. I would bet there are few if any permissive blocks in Florida or other flat places in the United States.
What? that's just flat out wrong. If you look at ANY track that has two way traffic and capture the flag signals (White Creek, Eaglepoint, CStp&P, Mill Creek to name a few of the biggest ones out there) all that is allowed into the block is one train at a time. Sure you can manually section, but that is the exception not the norm. The real congestion is a result of unmanaged traffic flow. People going where they want when they want with out any multiple passing, priority overtaking, or means to coordinate the flow.If you enforce a one-train-per-block rule your railroad will get constipated on a busy day as engineers stand at red signals waiting on a slow-moving train up ahead to clear the block.
Our operational traffic more or less random, we follow no schedule and only on a few railroads do we dispatch the traffic by radio on the main (CIG for Example). I'll solve that problem next year...