That would reduce the ROI, because doing it often (every day) approximates continuous exponential growth (e ^ x) while doing it in batches reduces to power grow

That would reduce the ROI, because doing it often (every day) approximates continuous exponential growth (e ^ x) while doing it in batches reduces to power growth (1 + r) ^ x. See the effect this has in the example given here: http://math2.org/math/general/interest.htm http://math2.org/math/general/interest.htm