Not a question of sarcasm, Richard, more of exasperation. This subject has been discussed many times, yet people still struggle with that bearing when there is no need. If the bearing is tight (not all are) then destroy it if necessary to get it off, but then ease the crankshaft with emery tape until the new bearing is a sliding fit. End of problem. As stated, there is no engineering reason for the bearing to be tight other than keeping manufacturing costs down by having wide tolerances. Worry about the bearing not being tight? On Ford Zetec engines the pulley which drives the cam belt, waterpump, alternator, PAS etc is not keyed to the crankshaft nor is it on a taper - it's not even a tight fit. If you tilted the engine sideways without the retaining bolt in place, the pulley would fall off. It is retained (and, unlike a bearing, needs to contend with considerable torque) simply by the friction created by the retaining bolt. The cam sprockets are the same - and they're plastic to boot!