Say, for example, Bloomberg and Biden reach the threshold and Buttigieg and Warren do not. Then Buttigieg’s and Warren’s votes would be discarded, even though together they might have as much as 28% of the total vote. If lesser candidates are included, as much as 40% of the vote could be simply discarded. Sanders, Bloomberg and Biden would then share the delegates, with the largest percentage going to the winner. This would give Sanders many more delegates than he would earn in a true proportional system without the threshold and the discarding of the votes of anyone who does not reach 15%. It’s the latter quirk that balloons the delegates for the winner and anyone else who qualifies.
Bloomberg may have reasoned that the election would come down to a contest between him and Sanders and that both of them would profit from the discarded votes. But that was always an unlikely scenario, given that Bloomberg is not on any ballot until Super Tuesday, March 3. There would be no reason to expect other centrists to drop out before Super Tuesday after participating in only two caucuses and two primaries, counting the South Carolina primary this Saturday.
Given the arithmetic of the primaries, the Bloomberg equation was defective from the outset. That’s not to say that he or one of the other candidates couldn’t make chicken salad from this mess. But the rules (and much else) favor Sanders.