Chuck,
Regarding your desire for your DSP to use shorter blocks of time when calculating a stockorder, thus enabling a more accurate and rapid response to sales, I agree 100%. I have wished for just that many a time (when I lost a sale or had a stockout that I believe would not have happened with weekly time units). Weekly "time buckets" are common in manufacturing software packages designed for material (parts!) requirements planning. I have "dreamt" of bypassing our ADP system's STK routine and instead importing daily sales data into some custom program that would use weekly buckets. I would then design my own ordering algorithms using standard deviation and other weighting criteria for each source. Then I wake up. The phone is ringing. I've got to get back to work!