I don't agree with that (topslicing). There's truth to the original stake element, it's an arbitrary number. Markets do have something resembling memory, more so the more they're based on confidence, so why shouldn't your plan be based on history?
More to the point, the amount you can safely bet has some relation to your overall wealth, wealth may have no memory but how much of it you have is fluid.
You think cows are undervalued so you buy ten cows, and a little while later the price of cows is double what it was. Listening to talk around the town, the chance of a crash is high, but you also think 3x is still entirely possible. The sensible thing to do is sell some cows now, let's say half, reducing your exposure and returning to an acceptable level of risk in terms of your overall wealth.
But should you have come late to this game, would you buy five cows at the inflated price? Probably not, because it represents not just the same stake, but the same percentage of your total wealth as the early bet, at a much higher risk. You could buy 2.5 cows at this point to achieve equivalency, but I suspect your half cow is only good for dinner.