I'm trying to fathom out what criteria makes it a reversal so far it is unclear.
Groningen stated a change of direction but that's not quite true as I highlighted that a change of direction has other meanings.
Crispy stated it goes in one way then out the other with crew change. That was confirmed by bb1 with my Vic and back example.
Now your saying it is a reversal at an intermediate station. I'd certainly be interested to know where crew change ends on a signal and or junction
I'd also like to know if it is a passenger perspective or traincrew because again, Origin and destination mean different things to me. I drive a service where it could be seen as a single journey but could also be seen as two separate services. Hence my confusion.
I'll be honest, I thought "reversal" was a fairly standard term with no difference in meaning between passenger and traincrew (other terms such as "change of direction" would have a difference in meaning), but the railway is one of those places with potentially a fair few different words in each region for the same thing.
Groningen is right from a passenger perspective - the train physically changes direction. But as you say, to a member of traincrew, this is likely to refer to the point at which the line the train is travelling on stops being up and starts being down or vice versa.
Crispy didn't say the train has a crew change. He says that the crew change ends. Which is correct, unless you're feeling particularly adventurous and want to drive the train from the (now) back cab to spice things up a bit, or have a natter and a brew with the Conductor.
I wouldn't say into (London) Vic(toria?) and back is a reversal, at least not for the purpose of this thread. Your inbound train terminates and then forms a new service which will start in the outbound direction. If your train then stopped somewhere en route and had to leave the same way in which it arrived in order to continue it's journey, then this would be a reversal.
It's not unknown for traincrews to change ends not at a station. On the Looe branch, trains leave Liskeard, pass over a junction, then reverse direction back over said junction, but the other way, towards Looe, requiring the crew to change ends. I've been on diverted XC services which have had to reverse near Severn Tunnel Junction, so driver has to change ends. And ECS, off the top of my head some XC Reading terminators go into the siding just beyond Reading station for the Driver to change ends, and if a Southbound XC service has to terminate at Brockenhurst, you have to do a shunt move to the South in order to cross over to the Northbound platforms. The driver thus has to change ends just past the junction at the South end of the station.
There will be services which are grey areas in terms of Origin and Destination (Merseyrail loop line services near me, for example) but the vast majority of trains go from A to B.