Anyone with a heavy recoiling double who reloads could do a test to see if crimping is needed or not. I can find no reason for not crimping any hunting ammo. Load a batch for range practice but don’t apply a crimp. Load both barrels but only fire one. Open and load the just fired barrel. Do this two or three times. Check the OAL length of the round that has been subject to the recoil but not fired. Compare that length to the OAL all the rounds were originally loaded to. Recoil is subjecting the unfired round to inertial pull that may increase its OAL. The only thing stopping the bullet in the unfired chamber, if it is being “pulled” by recoil, is the bullet’s ogive shoulder at the shank contacting the lands in the leade. I think a variable OAL caused by inertial pull would not be the best for accuracy and may increase pressure if the ammo is loaded for some freebore jump and inertial pull forces the second barrel, unfired bullet into contact with the lands.
This phenomenon is common in revolvers and one of the reasons revolver ammo is always crimped.
Additionally, crimping prevents bullets from being setback during rough handling.
The LEE FCD is the best tool for applying a consistent crimp and will not decrease or cause variable neck tension as common roll crimping sometimes can when done by the crimp shoulder in the bullet seating die.
I have never crimped .375 and lighter. I have not had an issue to date. If I loaded for my Lott I would definitely crimp.