I understand about the ratios; this crank was designed in the era when people were using five or six speed cogsets. The half step made sense then, because it effectively gave you ten equally spaced gears (when done right!) But the shifting issue. As far as I can tell, it is because the rings do not have the ramps and formed teeth that help the front derailleurs move the chain. I have several bikes with the TA cranks, and I can attest that big jumps between the chainrings can be awkward. It's tolerable on a double (I run compact doubles on a couple of those bikes) but on a triple you can feel the front derailleur protesting.