i think the point is
he cannot scale the volume up since it would distort the market and thus the bot would stop working..
It isn't about volume, a 2.5% per day increase simply isn't possible. You can't do it with pennies either.
Its like saying you built an electric car. Cool, I'm following you. But then when you say it has 1000km range everyone stops listening (or you should). An electric car is has a hard limit by the joules per gram in your battery. A trading bot is limited by the stochastic process.