I think I was pretty clear. You setup your pebble watch via openid connect/oauth like any other API client. No nag popups, manual Bluetooth pairing, etc.

That's way more steps, making it more annoying to set up, not less.

Only if you consider connecting to a single phone. The advantage of what I’m proposing is the watch would automatically work with whichever other Apple devices are on your account.

No prompts. No interoperability with non-Apple products or services. Maximum security. Minimum interaction with unwashed masses.