? Why.
I would have thought that it was better to keep your options open. Use the T&G's where you need wider panels - table tops, bench sides and top, doors, shelves, etc. For narrower uses cut to size.
I use a lot of repurposed timber. One worry with floor boards is the nail holes. My solution is to use a plug cutter from Veritas and just drill the holes and glue in a matching plug, aligning and matching wood grain as far as possible. Turns a problem into a feature!
Cheers
Graeme