Yes, it's possible to survive in forex trading using big lot size with big capital, but to do it in a small capital, it might be difficult, although some skilled trader can do some wonders trading with small capital and turn them in to big profits. Sometimes the debate is not all about the lot size, it's all about the skill and experienced of the trader, if he or she is capable to withstand the pressure of high risk trading in small capital. If she or he can do it, why not?