may I explain my point: as much as I looked into oracle's metalink - quite little information was available on histograms. So make inference yourself.

(yet another example is SDO: we were quite happy to use it in a project untill it came out a memory leak issue. The symptoms were the same: no answers on dbasupport and very little articles on metalink, etc. So we just droped and replaced SDO with 3'd party product which is really good on that task.)