It’s hard enough to see how this vote-throwing arrangement has a chance in coming contests. But the deal would have had zero effect on past primaries, even if the two candidates shook hands weeks ago.

Let’s presume this deal only became possible after Marco Rubio dropped out—after all, the Florida senator’s last-ditch efforts to direct support toward Kasich were rebuffed. The next major contest was Arizona, a winner-take-all state that Trump won with 46 percent of the vote. Kasich and Cruz, as much as they tried, only got a combined 40 percent. No amount of vote-swapping would have changed that outcome.

New York, the next stop in our time machine, looks a bit more promising. Kasich won parts of Manhattan and Queens in New York City, albeit by a mere 70 votes, and came close in several counties upstate. Some extra juice from Cruz could have pushed the Ohio governor over the top in a few districts, though probably not enough to top Trump’s 60-percent lead statewide.

Paradoxically, Kasich could have actually performed worse in an Empire State primary without Cruz in the competition. The polls don’t uniformly agree, but at least one pre-election survey showed the average New York Cruz supporter would pick Trump, not Kasich, if forced to drop the Texan.