Probably a poor word choice due to it’s wide range of interpretations (many of which are negative). The MMR algorithm is not a scam. It’s a carefully crafted system which endeavors to maintain matchups that are as fair as is reasonably possible based on the programmed factors that the developers believe are a good determination of player skill level.
Also probably a poor word choice. Carnivore was quite clear in that he wasn’t not trying to “tank” his MMR in an effort to get easier matchups the following month (see blue FAQ). He was achievement hunting, a perfectly reasonable playstyle which ought not be likened to “tanking” and certainly not to “scamming”.
And as a result, much of this thread was confrontational, which makes constructive discussion difficult. (I have been guilty of this myself in the past).
As to the substance, I don’t necessarily agree that the system is designed to spot trends in playstyle, like achievement hunting, in order to factor that into the MMR adjustments. I think it’s more likely that Carnivore did, in fact, experience a big drop in MMR due to consecutive losses from his achievement hunting playstyle, thus earning him matchups against weaker and weaker opponents. However, when the next month came, his MMR was adjusted up to his more historical level, thus matching him against comparably skilled opponents, in accordance with this:
And while Carnivore did not “intentionally tank” his MMR (i.e. causing it to drop in order to start the next month with easier matchups), his MMR did tank on it’s own due to the natural tendency of achievement hunting to result in very poor win rates.