Well, as a moderate Independent, I really hope this plan never takes shape lol. I don’t want to be stuck voting for far left or far right candidates.
That being said, I’ve seen people toy around with similar ideas in past elections and always wondered why this hasn’t happened yet. I know people who have switched form Indie to Rep or Dem just so they could vote for someone they really liked in the primaries — that’s not an uncommon thing as far as I can tell, though I’ve never done it just because it felt deceitful to me somehow. And I also remember when Rush Limbaugh suggested trying to draw out the Democratic primaries in 2008 by switching sides and voting for Hillary after Obama had already taken a decisive lead (he thought a longer primary could cause a major rift in the Democratic Party and discourage their voters). But I don’t know anyone, Republican or Democrat, who tried to sabotage the other side by switching parties and voting for the absolute worst candidates in the primaries.
Maybe it hasn’t happened because it’s usually quite difficult to rally voters around local candidates. Lots of people care way more about presidential elections than local races, hence the lower turnouts during midterms. Heck, I recently saw a poll that said that more than one in three Americans don’t even know who their local representative is. It would be hard to get people like that to do what you’re suggesting in this post.
And when it comes to presidential elections, it’s a lot harder for shady candidates like Roy Moore to get past the party gatekeepers, so I’m not sure you’d even get the chance to vote for someone like that in a presidential primary. Trump is an exception in that regard. Without his money and notoriety, he wouldn’t have survived against the GOP establishment.
That said, it would truly be an epic moment in politics if you could pull off the plan you’ve laid out here. I personally don’t think it’s feasible, but I also didn’t think Trump could beat Hillary. Shows what I know, lol.