What great examples.
Let's be honest. The LNWR had a lot of locomotives to find names for, and giving a loco a name is a lot more fun than just sticking on a number. It even gives us something to post about a 100 years (almost) after the LNWR ceased to exist!
I think it does more than mere fun, certainly for me.
For a start, it gives the locomotive 'pesonality' - you remember a name, it's much more difficult to remember a number. (I'll come back to this below.)
And more: somewhere, out on the web, there is a photo of one of the four Black 5s that were named, sitting in Kentish Town shed. I think it is 45154 Lanarkshire Yeomanry. It's a side on shot, framed (I think) in window or maybe the shed walls. It's also very clean.
The nameplate stands out to the eye, and adds an unfathomable grace and beauty to the locomotive.
(OF course, I don't know how much that might mean, or not, to the average passenger, but the 'Big Four' clearly thought it had value.)
But back to point 1, which just happens to involve 45154. I have a very clear memory of seeing this loco for the first (and, I think, only) time, aged 8-9, in 1960 or 61. It was about 12.20 one day, and I was sitting at the north end of Bedford Midland Rd station, then platform 4-5. There were two, perhaps three of us, and someone - might have been me - asked if anyone had ever seen one of the named Black 5s. (At the time, as I recall, three of these were Scottish locos, and the other, 5154, was allocated to somewhere in the Liverpool Division, Bank Hall or Allerton or some such.)
This meant none of us had these elusive Black 5s underlined in our Ian Allan ABCs.
Now in those days, the standard MML semi-fast service was 1 train per two hours, and right then, during this chat, we could see, through the arches of Ford End Road Bridge, the 12.25 (ish) down semi-fast approaching the station from the south.
And what, thirty seconds later, should chug into platform 4, a few feet from us, but 45154 Lanarkshire Yeomanry!
That was some synchronicity - not that I knew the word at that age
But had it been 45153, or any other 838? unnamed sister locos, I'm fairly sure it would have been soon forgotten, as a several-times-a-day event.