In reply to millsy:
For the experience —> Rackwick bothy
For simplicity —> in a day from Stromness
When we did it we got the boat over first thing, got the taxi/minibus across and walked in and climbed the route. We then walked back to Rackwick, dumped our sacs with the minibus driver and asked him to drop them at the cafe. Meanwhile, we ran across the path over the obvious col. There was plenty of time for us to do this and have a coffee before catching the ferry back, and that was the 4.30 ferry so not the last. It’s not especially high pressure or stressful to do it a day. For the rest of our stay we very much valued being on the “mainland” - more to do.