it the Mk B XVI was not a pinpoint precision bomber....... it carried the cookie and dropped it from considerable altitude with all the (in) accuracy that involves. It flew missions in squadron strength against significant strategic targets.
There is a difference between the 4,000 lb HC bomb, or 'cookie', and the 4,000 lb MC bomb, which could, and was, used for precision bombing.
The cookie had all the aerodynamic qualities of a tumbling barrel. Actual weight was 3,940 lb, with a charge to weight ratio of 75%. Mosquitos usually dropped it on area targets from medium to high altitude.
The 4,000 lb MC was used from mid/late 1944 for drops on both area AND precision targets. It was usually dropped from higher altitudes than the cookie, because of its more predictable flight path. It had a charge to weight ratio of 58% and was similar in construction to standard GP/MC bombs. Actual weight was 3,764 lbs.