@@sydfixesbikes great job on the new channel. Even on stuff I know how to do I've learned tips and easier ways to do things like with the gravity bleed instead of syringes
The sealant dance makes it easier to get the sealant along the sides where the tire meets the rim which helps the tire seal. Spinning it generally just lets the sealant run along the bottom of the tire...
And...eventually have a clogged valve. Don't forget, for long rides you will want to bring tire patches. And sealant. And a valve stem. And a tire boot. Some thread for stitching tears. Tire levers. And a....TUBE. I sure am glad tubless set-ups are so light.