[ctdonath]

About a year (?) ago, someone did do a study of Lego manufacturing variance. They throw away a lot of bricks to keep the variance very small. Granted it focused more on fit than compressive strength, but should help you get nearer the answer.

[2muchcoffeeman]

I hope the plastic can get recycled to make more bricks.

[mattmillr]

It's ABS, the same plastic that some 3-D printers use, so they should be able to just chip it up and feed it right back into the hopper for the molds.