Originally Posted by
veganbikes
Yes you could use the wrong shifter and make it work. Would I, no especially when the proper shifter exists. The reason you DON'T use the wrong shifter is you have to lock out so it doesn't make that third shift which most people would know would go outside of the cranks which is bad and overtime you are likely to break that lock out and you have the problem. Yes you could tell someone hey your shifter has three shifts (or five with trim) but don't use that third shift and guess what someone will forget make a mistake or maybe a mechanic could screw it up not knowing or not noticing. It is simply not worth it personally to recommend incorrect parts except in an absolute emergency but this is not one of those times.
Why do you doubt it? You don't think people would counterfeit a part from a company? Is it that far fetched because they are Taiwanese? KMC is a Taiwanese company and people counterfeit their stuff so why is this so far fetched? Unscrupulous people will counterfeit just about anything and sell it on all these 3rd party platforms it is not some something that only happens to Brand A and B and brand C is left out. They fake Sharpies, a simple low cost permanent marker for cripes sake.
If you are using position 1 and 2, position 3 (high) is blocked by the H stop. You can't get there without putting so much force on the shifter that it would break something. I think Shimano sold a brifter at one time marketed as 2/3, so this is hardly the "wrong shifter", anymore than using a 7700 to shift 8 on a 7400 derailleur is (also per Shimano spec).
The seller I posted has 5 out of 5 stars and the price is only moderately lower than retail. There is no reason to believe that they are selling fake Microshift, of all things. People buying Shimano have much more to fear in this regard.