If it's the one just after Armley Moor tunnel allowing trains to go on to what would be normally the Bradford line, the Grand Central Train I was on a couple of years ago used it.
Because of works in the Mirfield area, we were diverted from the usual route from Interchange-Halifax-Brighouse via Bramley and this crossover, stopping to reverse past the junction with the Doncaster line. After changing ends, the driver then proceeded via Wakefield Westgate down into Kirkgate and the normal route.
Seems a weird shunt that. I would have thought he would have run out on D road onto the Holbeck curve and then just came back out again.
There used to be another crossover near Whingate Road bridge which enabled trains to cross over to the coal yard on Carr Crofts. I think it may have been a trailing crossover. Remember 31’s on coal duties in the yard when I was a kid. There was a weighbridge on site so that the lorries taking the coal out could be weighed, which was usually domestic supplies.
Only used it twice, once on a Diverted GC to enable us to reverse at Whitehall Jn, and the second time on a late night Northern.
Its not a ideal crossover as its a slow speed crossover, and puts you "facing road" on Line D into Leeds which prevents anything Leaving Leeds towards Bradford Interchange until you arrive at Leeds, also limiting anything from Leeds towards Wakefield W to use the Copley Hill Chord only. Which is probably why its very rare to use it