Look carefully at J-wagons various machine builds, page 7, post #69. He clearly rides a lot, modern and old.(see his carbon 29-er mtb rocket) You will notice that no matter where his seat is, modern or old, his bars and hands are positioned slightly above or below his seat height and for the most part in front of his head tube. This keeps him in the center-forward position on his bikes, which is a good thing when trying to up the performance levels beyond the bike path. Necessary. The up-in-the-air hands "apehanger" position, while comfortable, limits your ability to stand up quickly to accelerate or climb and the front end of the bike will want to "lift" or there will be no room to comfortably position yourself forward over the front wheel without your hands and bars getting in the way. If off-road riding a custom built prewar 26-er frame, your hands should ideally be in front of the frames' head tube. Hands high in the air and swept back certainly feel good in the flats cruising, but don't expect this to help the bike perform better.
In regard to the 21st Century Hawthorne, it is a unicorn bike. It started as a Long wheelbase 1931 28-er frame/fork. Long rear stays on the frame allowed fat 26' rear wheel but the fork did not. I went 26" by installing the shorter custom Shelby front end. The result is a very low BB height, super steep angles for both seat and head tube while maintaining a longish wheelbase. Understand also this bicycle was initially fitted with an original 28-er fork. In total, the frame's angles, overall light weight and fast wheels make the bike ride like no other 26-er I have. Clipped in, over the BB and "in the pocket" is how I fit this bike. Result? Rocket. Catching or joining groups of roadies in packs at 20mph in the flats is easy with this bike. The front Shelby fork issue of splaying out when standing up has been recently resolved to a large degree as I installed a heavier spring with more preload on it.🛠️ The cool thing about building your old steel frames/forks up is that you can choose your parts to specifically create a bike that fits you and the position you need for the riding you do.