Sourdough Sorted

I was going to a friend's house for lunch a couple of weeks ago and decided to bring a sourdough loaf to help things along. As you know my started has now been alive for almost a year but as I don't make a loaf every day I have to reactivate it a few days before I want to bake the loaf. It sits in a cupboard in the kitchen quite happily. When it has been left for a while it separates, on top there is a brown liquid and underneath a creamy sludge (sounds good doesn't it?). This sludge is the stuff I need, you take a couple of tablespoons of this (discard the rest) and add 100mls of lukewarm water and 125g of strong white flour (from The Handmade Loaf by Dan Lepard), mix and leave for 24 hours. Next day you discard about three quarters of this and add the same quantities of water and flour and repeat this the next day. As the natural yeasts come alive again it starts bubbling and once that happens it's ready to use, if I want to bake a loaf at the weekend I usually start this process on Tuesday evening.
I guess it is a bit time consuming but it's worth it in the end. I decided to do the main mixing, kneading, proving on the night before (it still takes about 5 hours, it's a slow riser the sourdough) and then put in the fridge overnight for it's final rise. First thing on Sunday morning I put on the oven to warm the kitchen and took the dough out of the fridge to come up to room temperature, about an hour. It then bakes for 50 minutes to 1 hour, not forgetting the steam to help with the crust.
It was a hit at lunch and what was left was frozen and was nice and fresh after defrosting. I do like making sourdough but I do wonder about those who make it to sell. It must be like painting the Forth Bridge, they just have it proving constantly, as one is rising another is being mixed. Hard work if you are producing hundreds of loaves a day. Worth it of course.