This is a beautiful, if scratchy video of BKS Iyengar, made when he was at his prime in 1977 when he was only 59!
Go to 12 minutes into the video where Iyengar is practicing with a small advanced class. An incredible Vinyasa with transitions from Ardho Mukha Svanasana straight to Bakasana.
Then there is that individual practice of balancing poses from Sirsasana II which is still taught in Calgary by Norman Sjoman. who studied with Iyengar in the 1960’s before Guruji became famou