Great Western Coffee Shop

Anyone know why Cornwall tends to get an hourly mainline service during engineering work periods (on the bits that are still open to rail traffic) as opposed to the normal half hourly service? During the rail replacement coaches and buses between Plymouth and St Austell at the end of March I had family/friends waiting nearly an hour at St Austell, after coming off the coach, for the next train westwards. A half hourly service (or better connections between road and rail) would have speeded up a journey which was already long due to a lineside fire near Paddington and to changing to road travel at Plymouth.

When a train is replaced by a bus, passenger numbers are decimated and you don't need as many trains?

The onward train from St Austell becomes a connection rather than a through service, so the train runs to time and if the incoming bus connection is delayed and just misses it - tough .... train has to run to time for local traffic, pathing, crew hours and operational stats.

Quite possibly, or trains are reduced during engineering work to dampen down demand? I suspect that incidents such as this one can also play a part in dampening down demand during engineering work (and increase Delay Repay claims), also as life carries on during engineering work I suspect many people may just find other ways to travel.
Yes, nowadays holding a connection, even for a couple of minutes, is less likely than it was in the past when the procedure was more common, especially if the alternative was a lengthy wait. If you pull into a station on a train or a rail replacement bus whilst your connection is pulling out I doubt few would feel like bursting into song about it, I suppose it depends on whether you feel like voicing constructive criticism or accepting the status quo about these things.