I could be wrong/crazy, but isn't this change correct?

9. The first request() call should be in the *foo(1) instance, as *foo(2) and *foo(3) are waiting.

10. *foo(2) yields its request promise back to *foo(3), not to *foo(1), which has already completed by this time.

The thunkify definitions as published will only work the first time they are called, after which the thunkory will continue appending to a shared args array, calling `fn` with more and more arguments.

To prevent this, the thunkory should clone a new copy of args every time it is called, and push the latest cb to that args array.

The explanation of the process() manual transformation function includes references to a "resolve" function that is not used in the example. 

It's clear from context that the explanation is referring to the "yield request" statement replaced by "return request".