The stock market is overly optimistic about US-China trade talk.

The stock investors are overly optimistic about the upcoming US-China trade talk.  Why?

This US-China trade talk is a mid-level negotiation which will just set the stage for the November trade meeting between Trump and Xi.  Therefore, there won't be any significant trade dispute that will be resolved in this August trade talk and the mid-level authorities are not empowered to make any important trade decision but to defer the decision-making to November.

Anyway, any decision made in this August trade talk can be easily revoked by Trump in November.  Thus, it is pointless to remain optimistic for any good outcome.