If my Stanford co-founder wouldn't have scaled back his involvement recently, we were just on track to apply for the YC fall batch. Now, when he is not there as technical co-founder, the situation does becomes different. Earlier, our chances would have been good as we brought in a decent balance of complimentary skills to the founding team - we could have managed w/o traction (if I may say so). But as a single non-technical co-founder, showing traction becomes a must-have.