Some people will tell you to use a 5.0:1 for deep cranks but after re-tying 10-12 times you end up gearing down into the fours because of how much line is on your spool. I use a 7 gear for pretty much everything except for 8-10XD's where I'll utilize a 6 gear and mayyyyyybe a 5 gear if I'm throwing 10XD's exclusively.
You must use a lot of line to retie, or a small capacity narrow spool reel for just a dozen knots to make a huge impact on effective gear ratio. A wide high capacity spool (like wide 200 size reel) virtually eliminates the issue.
Figure 12 feet for 12 knots, or 4 yards. Even a 100 size reel typically holds 120 yards of 12# test, which is rather common when cranking. That's a 3.3% change in line capacity, probably not very many wraps on the spool, so I think you may be exaggerating the loss of 12 knots tied. Use a 12-15 foot leader, tie 6 times, then replace the leader; that should put you taking ~6 feet off, then putting it back via a new leader.