The weapons specialty video said you use crushing tide to activate spirit blade when at 5 chi. Spirit automatically activates at 5 chi. And crushing tide is only usable once spirit is forged. It didn’t work like this the last time I played. The tutorial video doesn’t even explain the mechanic correctly.
The mechanic got changed with the weapons balancing pass. It was huge but not all encompassing. They didn’t update the tutorial video though, that is correct.