I not old enough to remember MacGovern, but I'm old enough to see how the Democratic Party has behaved since MacGovern. And it seems to me that the Democratic Party has sort of internalized a sequence of "traumas," leaving them with the sense that they can't be straightforward with their idealistic goals, because otherwise they'll lose elections.

For instance, it wasn't okay for any high-ranking Dem politician, including Obama, to explicitly express their support for gay marriage, because the nation wasn't ready for it. But when things suddenly break in that direction, it's fine if Obama says that he suddenly changed his mind about it, even if it's completely unbelievable.

So "establishment" Dems can only say things like, "I believe in non-oppression regardless of sexual orientation," or "maybe gay and lesbian people should be able to engage in civil unions that are just like marriage but not called marriage," while "progressives" are free to just come out and say that gay people should be able to be legally married.

The thing is, young people tend to be idealistic, and Sanders's appeal with young voters derives in large measure from his willingness to take an idealistic stance on several key issues. The dynamic on the left is that Hilary is "dishonest" and "untrustworthy" in part because the Dems fear that having ideals is unpopular, while Sanders is "unelectable" because he clearly professes to having goals that have been batted around for at least 50 years.

So the sort of absurd idea expressed in the linked article is that the liberal movement would benefit from having idealistic goals that are clearly stated, but that these goals would have to be institutionalized around someone like Sanders, because doing so would sequester holding ideals from winning elections.