I you look at the photo in post#6, you can see Shimano Total Integration printed on the shifter pod body, the shifter pod is integrated to the lever, as in it cannot be removed and installed separately. STI has nothing to do with being able to shift with the brake lever, its the integration of the brake lever & shifter into one assembly.

For MTB's this culminated in the DCL concept (where the shifting was done with the brake lever), which lasted for a single generation, now MTB STI's are available upto Alivio level, from Deore on, you get separate shifters & gear pods.

Currently, Ispec is the closest you can get to higher end MTB STI , by mounting the shifter on the brake levers handlebar mount, by using compatible brake lever & shifter pod cover assembly. SRAM use a similar system with Matchmakers

For staying out of a thread, the is BF, you have to have your say