I agree with you, this doesn’t “complicate” anything for Roberts. If anything it will look to ordinary voters like inside politics gamesmanship. I just don’t see any groundswell building for a country club Republican masquerading as an “Independent” as a halfway house to becoming a Democrat. Especially in a Republican year with an unpopular Dem President. This guy must have a miniscule base.
The most reliable Dem voters can’t do anything but vote straight party. If they have to vote for individual candidates they are going to get confused.