From my vantage point this looks like simple greed on the
part of Mr. Dyke for the sale of another set of drawings.

Am I missing something? Has anybody actually seen this
notion applied as a legal precedent in the past?

Who is being greedy here?
What prevents the plans from being resold indefinitely each time the
possessor dies and the estate tries to make money off from the sale?
Mr Dyke owns the rights to the plans. If someone wants to buy a set of
plans and build the aircraft, they should be purchasing the plans from
Mr Dyke, not an estate of someone who had purchased a set of plans from
Mr Dyke.