Not sure if it can be called a pivot when it was in the original release of the software. Payment channels aren't in the white paper but they were in the first

Not sure if it can be called a pivot when it was in the original release of the software. Payment channels aren't in the white paper but they were in the first public release and had dedicated opcodes. That first implementation wasn't very practical nor was it secure. The fact that modern payment channels are implemented with other opcodes may be a pivot in implementation but not in concept.