Not all ideas, no matter how world-changing, can be turned into a full company with just one founder and roughly zero cash. For young founders, 15k, partners and a basic support system can make a world of a difference.
edit: The real deciding factor for me though will be his equity equation.
Right, but it's usually possible to find another, simpler idea - even if it's just consulting - that will generate $15k and bring you in contact with potential cofounders or customers.
edit: The real deciding factor for me though will be his equity equation.