According to the fragment of the Arbitrage USD "10" overview, (please click the link below)  it seems to be a great arbitrage occasion between vcxUSD and a handful of other exchanges (Bitfinex, bitstamp, btce, coinbase, hitbtc, Kraken, lake, okcoin):

http://www.bilder-upload.eu/show.php?file=8c69fa-1463903698.gif

Does anybody know if vcxUSD does support USDT (Tether)? So that we can transfer USDT between vcxUSD and Bitfinex (bitstamp, btce, coinbase, hitbtc, Kraken, lake, okcoin)?

Or does the fact that an arbitrage win between this exchanges are so high indicate that USDT is not supported between this exchanges? As if it would be possible, the arbitrage win would be much lower?

Why seems the arbitrage win potential between the mentioned exchanges so high? Is there any problem to put it in the praxis? What is the hook?

Thank you for clearification. Would very appreciate your answers.