This is why I think having more than one copy is a good idea even if you have LPP.

For one burned in dirt removal. If there is dirt on one frame of one
print but not on the other that dirt should be removed. as the dirt is print specific. If dirt is on both prints its more likely something that was on all prints and you may want to leave it. Also I said this before.
Some one may make a program that can put 2 frames together and cancel out grain not on both prints and leave grain on both prints, as will as putting the details missing from 1 or the other print.