Complex sentence: The haulage was provided more to keep up route and traction knowledge for the 87s than because of unreliable 325s, and although recently the powered vehicles have been removed from some sets, they have now been re-instated.
Split into simpler sentences: The haulage was provided more to keep up route and traction knowledge for the Class 87s than because of any unreliability with the Class 325s. Although the powered vehicles were removed from some sets, they have now been re-instated.