ETC wasn't arbitrage, it was a flash sell on hitbtc (3 times in every 15 mins in a row). I just knew that buy volume on hitbtc isn't enough to quickly get out of position, as i need bitcoins to trade, that's why i sent them to bittrex and sold immediately .
For low volume coins arbitrage works nice, but you need to be careful.
ahhhhhh, i didn't completely read the bottom of your post. man, that's some good work.