The greatest ideas are often, when analysed, very simple- simple enough to be memorized by an average person.
This leads to the possibility of an amusing "counterfactual alternative history" contest, alongside some experimental archaeology.
The contest is in two parts. Firstly, authors must describe in simple terms the concept underlying morse code, or the verge escapement, or the screw propeller.
Secondly, a contestant must memorize the information, and then "time-travel" back 2000 years and, using available technology and materials, construct a functioning exemplar.
A smooth metal bowl coated with silver is the basis of a reflecting telescope; what if the Romans had constructed an optical semaphore to send morse code? Calcium carbide is fairly simple to produce, and would have yielded acetylene lamps. A galley with a screw propeller would have easily outmanouvered one driven by oars.
Ths could be the basis for an educational TV show.-- 8th of 7, Jun 28 2016 Connecticut Yankee Steam Engine Challenge Connecticut_20Yanke...0Engine_20ChallengeI got yer screw propeller right _here_! [bungston, Jun 29 2016] Science fiction authors already write about such things, in a genre called "alternate history", often involving a time traveler. The classic work in the field is "Lest Darkness Fall", by L. Sprague deCamp, written in 1939.
These days a fair number of authors are writing alternate history stories. It's a popular genre.
So this Idea might possibly be considered well baked....-- Vernon, Jun 29 2016 random, halfbakery