Despite the fact that most of the jokey scenes in this story were never recorded before cameras, their presence is still felt. The description of The Doctor's improvised helmet, complete with a chunk of old table top, would have been difficult to take seriously. Similarly, and in a scene that actually was completed, The Doctor pins a medal on Romana after the latter comes up with a brilliant idea, and later, when time is supposedly pressing, wastes time with a humourous speech before Romana (always the straight man) snaps at him to get on with it.
These scenes hammer home the point that, although intended to be the centrepiece of Season 17 and to be a fitting swansong for Graham Williams, Shada would have still been laced with the undergraduate humour that had been so prevalent throughout much of Season 17. What's tragic about the fate of Shada is that, after two consecutive years that saw Williams struggle to make ends meet before the end of a season, finally learned from these tribulations and socked enough money away to make the finale a much stronger story, only to have the rug pulled out from under him by those above him.
Graham Williams is, perhaps, the unluckiest producer in Doctor Who history. Forced to follow the hugely successful, yet hugely expensive and controversial, Philip Hinchcliffe era, Williams was behind on the count before he even stepped up to the plate. His stories were strong, for the most part, but intended to purely entertain and amuse as opposed to frighten the children that his predecessor was so good at (and received reprimanding for). By the end of the era, though, the programme had started to become a bit stale and bloated. A fresh start was needed to rejuvenate the onscreen product, and yet still maintain the high viewing figures that the programme was achieving at the time.
The man entrusted with this task was John Nathan-Turner who, alarmingly, would be the only producer the series would have for the rest of the run of the classic series. Bring on the 1980s.