Limey -
Steam locomotives were very rarely seperated from their tenders as that is their fuel supply. They didn't seperate them to turn them because they would have to turn and move and store the tender seperately. Much more labor involved. They kept their tender attached in the roundhouse because steam locomotives fires were kept lit and low so they would be ready for service. It takes quite a while to build a fire and bring the boiler up to temperature on a steam locomotive. Turntables had to be long enough to handle the longest locomotive and tender used at that location. Therefore turntables were rplaced with larger ones as lager power came into use. Hope this answers your question.
Steam locomotives were very rarely seperated from their tenders as that is their fuel supply. They didn't seperate them to turn them because they would have to turn and move and store the tender seperately. Much more labor involved. They kept their tender attached in the roundhouse because steam locomotives fires were kept lit and low so they would be ready for service. It takes quite a while to build a fire and bring the boiler up to temperature on a steam locomotive. Turntables had to be long enough to handle the longest locomotive and tender used at that location. Therefore turntables were rplaced with larger ones as lager power came into use. Hope this answers your question.