I'd be the first to admit that I don't necessarily know that a price reduction would boost profits, but I would add that even those in a better position with more of the facts than myself do not necessarily know that they won't. This is why I call for a bit of low risk experimentation.
Taking the lowest selling game out of 14 titles and reducing the price in a temporary month long sale ought to present very little risk, being that the move almost definitely cannot lower sales. Assuming the worst case, where all jeff's games are selling equally well and no gain is sales is forthcoming, he would be at the very most out ((1/14)*.6) of his total monthly income, or 4.3% for one month.
Note that this is for a total failure, in the worst case scenario. I concede that I don't know whether or not his finances are so grim that he can't risk this.
The potential gain, on the other hand, is incalculable. What if his profits increase by 10%? 20%? 100%? It would seem to me that the potential gain outweighs the risk, so long as he can afford to risk that 4.3% of one month's income on the venture.