Up shifts from the Granny would take place at the crest of the hill ..
I personally have no need for, STI but many would not go without..
their newest Left/FD brifters are suposed to be trim-able.. the previous has 1 position per chainring
[a solid ker-thunk]
so trim after shifting approaches the user control of friction shifting..
to reduce the chain scraping the FD chain cage.