AFAIK, blue and white Alps switches do not have the same part number. Blue Alps is part SKCMAG (contemporary with the elusive SKCMAF cream tactile), while white clicky Alps appears to comprise two separate part numbers: SKCMAQ (pine) and SKCMCQ (bamboo). I don't know for certain, but it seems quite telling that the same datasheet depicted yellow linear (SKCLAR) as pine, and white clicky (SKCMCQ) as bamboo, while white clicky in 1994 was given as SKCMAQ, pine. It looks like the removal of slits was significant enough to warrant a new part number, especially as the change did not appear to occur across all the factories at once.
The sheer fact that Alps changed the part number means something. MouseFan and Sandy have both mentioned the factory application of dry lubricant to early generation switches, and my amber Alps switches did indeed have some sort of dark substance on both sides of the slider (while Sandy's blue Alps Acer keyboard appeared to have it applied to the sides of the slider).
Forces in switches are complicated. In a linear switch, Hooke's law should tell you the force required to depress a spring by 2 mm, but you have to bear in mind that it also takes a certain amount of force to defect the actuator leaf in an Alps switch. In a clicky Alps switch, the click leaf imparts a significant portion of the actuation force; once you've cleared this point, that force is released and you've only got the return spring left. In blue Alps, this drop in force is quite considerable: the return spring is only 45 cN or so, despite having 70 gf (ca. 68.6 cN) actuation force. White Alps did appear to alter this balance; for example, Alps may have changed their materials. White Alps appears to have a slightly reduced pretravel, which will make a switch harder to press.
Edit: somehow managed to submit that before I was done.
And yes, Bob is confused. "I took a white and a blue switch, both have the same Alps # on them" — eh? How long did it take him to pair up a blue and a white switch with the same mould numbers? For me, the reverse was true: I never noticed that ALL Omron B3G-S switches say, well, "B3G-S" on them : ) I was just assuming that was the mould number, as I only have the one switch.
Granted, the difference in condition between different keyboards substantially exceeds the difference between blue and white. There's also the suggestion that humidity affects the feel. Blue and white are fairly similar, but my blue Alps keyboard definitely feels better than either of my white Alps keyboards. I also tried making a fake blue Alps keyboard by mixing parts of blue and black Alps, and it just doesn't feel the same — the end result felt like white Alps, and I suspected it may have been a change to the parameters of the actuator leaf, and I know the stamping changed. However, that could also be my fault for assembling the sliders back to front, as I since learned that they're not reversible (though they'll go in the wrong way just fine).
TL;DR: It's complicated, but no, they're not the same design of switch. It also depends which flavour of white Alps switch you have. MouseFan believes that the quality dropped around 1993, and I can easily believe that.
