Lobe seperation is just a way of changing the amount of overlap the cam has without changing the cam lobe duration. With a wider LSA you could goto a cam with more duration and have the same overlap as the smaller cam with a tight LSA. the whole cam profile , duration, LSA, and ICL need to be looked at as a package to identify the opening and closing points of the valves in relation to the piston position, and those numbers will vary depending on application, compression ratios, RPM range, and the intake tract and exhaust tract flow rates (and flow velocity.)