Re: Nailing reclaimed flooring
If it is flooring made from reclaimed wood, you can fasten it any way you want; if it is old flooring, it has already been penetrated by nails at regular intervals, and so may have running splits, etc. A flooring nailer doesn't split lumber because the "cleats" it fires are so slender, but where you may need to nail could correspond with a pre-existing defect.
Pre-drilling and hand nailing floorboards is an excruciatingly slow process compared to firing the nail gun.
If you trust the installer, let him do what he believes to be best.
Remove not the ancient landmark, which your fathers have set.