Nels says “That is exactly what I was wondering about! With a single sheet, you can
only snug up the mizzen sheet to line up above the boomkin/bumpkin or
loosen it off the wind but you can't pull it to windward to kick the
stern through a tack.”
If you think you need to backwind the mizzen to tack I say you aren’t letting out the main at the right time. Accelerate into the tack and then slack the main. Trying to keep the main in during a tack like a fin keel/drop keel/daggerboard boat is fighting the design except in strong wind. You get the same problem of losing speed and gaining leeway if you haul in the main too soon after tacking.