Here's a new can of worms: Since the proposed idea is to situationally cut back on your tech rate so you get a lot of overflow (probably from tech that is being researched with a 1.4 or 1.6 modifier) which gives you a boost in your first turn of researching your next tech, how about having no (or less) overflow so you don't dump "1.0" or "1.2" overflow into a "1.4" or "1.6" tech?
Example time. You have researched Fishing and The Wheel, are about to finish Agriculture, and plan on researching Pottery next. Fish, Wheel and Agr are all prereqs to Pottery, making it (in this situation) a 1.6 tech. If you just plow on through Agriculture at 100% and have some overflow, your first turn of 1.6 Pottery research will be cluttered with 1.0 (or maybe 1.2 if techs without prereqs are still "1.2s") overflow.
I can't test this out yet (waiting on video card and RAM) but it seems feasible. If you can slingshot for more overflow then can't you line it up for less? This would be really doable if you can figure out how many beakers you need to finish a tech. I know city screens at least show how many beakers each city is pumping out but I don't know if there is an empire-wide beaker count.