Explicit await and promise semantics are useful incase you want to, say, start multiple async calls instead of awaiting one and then the other. But ok, lets sa

Explicit await and promise semantics are useful incase you want to, say, start multiple async calls instead of awaiting one and then the other. But ok, lets say you just want await to be implicit in some cases... Do you actually want this? Currently, you can assume that a function will not change threads mid execution, and that that thread will also not be used to execute other things. Implicit yielding breaks that assumption. Cooperative multithreading becomes impossible because it's much hard to reason about when a method call will yield execution or not.