I don't understand the Sanders' surrogates "post-Pete-dropout" strategy

[Progressive2020]

86. It Is A Real Concern

I personally like the idea of Medicare For All, Green New Deal, $15 Dollar Minimum Wage, etc. The problem is that the standard bearer for these ideas is admittedly a riskier choice, given the reasons you state- leftism, oppo research etc. While I like the bold policy ideas a lot, and think that they would sell well to working people in the General Election, Sanders might be more vulnerable to attacks in that Election.

Joe Biden is on the other hand, not as controversial as Sanders, and is more measured and realistic. So, I would say that Sanders is the riskier candidate versus Joe, who is the safer bet. The question is what do voters want? Do they want big ideas and bold proposals, or is that too pie in the sky? Joe says he proposes results, not revolution, and that might be a winning strategy. It is a matter of how cautious some voters might be. Frankly, I would like to see a real debate between just Biden and Sanders on this, so it can be hashed out and the voters can make up their minds.