No, you can't time what happens on the mis-speculated path itself. What's leaking the information is the change to the cache state which is observable after th

No, you can't time what happens on the mis-speculated path itself. What's leaking the information is the change to the cache state which is observable after the original mis-speculated branch is resolved (by timing subsequent accesses to addresses that alias in the cache). You can also observe changes to the TLB state, though - so you'd have to do the same buffering-and-commit dance there as well. Maybe you can also leak data through the BTB or RTB (double-Spectre!), or by tieing up particular execution units conditionally which is observable by a sibling hyperthread?