Wow, great vids.
Were you first exposed to two man in Germany DL ? I've long done this, with a number of partners over the years. But have never seen it done by folks trained in the tradition it comes from.
Of the species you list, I've only had issues hewing Beech, and that not consistently. Ash and Hickory hew nicely but check and wind a bit much for me, and I avoid their use as a framing timber.
