In general, it's a mistake to alter the saddle fore-aft position to correct the reach to the bars. The fore-aft saddle position relative to the bottom bracket should be determined based on the proportion of the rider's weight supported by the handlebars (i.e.move the saddle back to reduce the weight on the bars, move it forward to increase the weight, bearing in mind that too much weight on the bars often leads to back, neck and shoulder pain). Only after that weighting has been determined should you adjust the reach to the bars by altering stem length.