Thanks guys, for entertaining a greenhorn's notions
Well, I was just thinking that if you had a colony at its happiest sugar percentage the entire ferment (around 2%), they might be healthier overall, and more capable of dealing with various other conditions, like the alcohol percentage rising. It also means they would be less stressed and you would get a different tasting product from a regular run, which may be good or bad depending on what you want. Also, you wouldn't have much die off near the beginning, and thus you'd have a larger population of cells, so you'd have more genetic diversity, and a better chance of developing heartier progeny.
As far as addition goes, of course.. you wouldn't want to add the sugar dry. You could work it out with a warm solution of saturated sugar + nutrients (except for any solids. I'd guess you could just pitch in a bit of yeast hulls from time to time) in a vessel that had a slow stirrer (just some cheap gear motor connected to an old kitchen aid beater), and a calculated drip rate based on how fast the yeast were working. Or you could just do it over a fixed time period, like 72 hours or so. Or if you wanted to ferment more slowly, use that time period instead. I'm guessing though that the sugars that were there would get fermented a bit more quickly, so you would have to play with addition rates. It might also make sense to sparge out your sugar solution for a few minutes with N2 to get rid of oxygen, but I dont imagine that would be necessary.
Another advantage is that you can control the sugar concentration at any moment, and thus control the fermentation rate and temperature, directly. You wouldn't have to worry about foaming over, or overheating. In fact, I would bet the temperature would remain relatively constant throughout the process. You could even do various things like forcing a bit of stress at points during the ferment, to see what effect it had on the final flavor and %ABV.
Since you're going through all this trouble, you could also stir your ferment slowly to keep it from stratifying. Unless thats what you want
If you did stir your ferment, it would probably be good to be a slow, and non shearing mixer (like a few stacked discs with a few holes drilled in them near the spindle, or even easier.. just a length of stainless wire shaped like a tear drop near the end)
Its definitely a bit complicated, but it provides a whole new toy to play with. And since this whole thing is just one, big, giant toy for me to play with, I like that
Now, this could also mean that the fermentation might be more likely to stick.. I don't know. But if you were adding nutrients along with the sugars in good ratios, I would think that would prevent malnutrition. Or you could put ALL the nutrients in the fermentation tank, and only drip over the sugars.
Thats pretty much the whole spark. I dont think this setup is any more complicated (less even) than making up a VM reflux still, especially considering it doesn't involve winding copper, soldering and brazing!