I am of the opinion that the external bearing design has superior marketing over the square taper design in 2007 - I am unconvinced that it is a better mechanical design. It seems to me that the bearings are supported by a thin sleeve that threads into the BB shell. The "standard" type were positioned inside of the BB shell which kept everything nice and "tight". It seems that the external design would allow for a lot more displacement of the bearings under load. The standard design would require the BB shell to deform for misalignment of the bearings under load - now you only need that thin sleeve that threads into the BB shell to deform. Am I seeing this incorrectly?
Unlike others - I'll be honest in saying that my degrees are in engineering, but my concentration is not mechanical design and my formal education is limited to a handful of ME classes.
I don't want to start a flame war - but I'd love to hear some intelligent arguments for both sides of this debate.