Complex sentence: Thus Harold Ridley benefitted from his own invention and the operational procedure he had pioneered but what was most pleasing to him was that he had it done in the same hospital where he performed the first operation in 1949.
Split into simpler sentences: Thus Harold Ridley benefitted from his own invention and the operational procedure he had pioneered. But what was most pleasing to him was that he had the operations done in the same hospital where he had performed the first operation in 1949.