Issues with unusual Color Spaces

It seems to me that the L*AB color space component and the LCH color space component are both buggy - even with Alpha set to 1 for both, the alpha of the resulting color seems to be driven by a different input entirely. In the case of LAB, the "A" channel (the SECOND one, not the first) seems to drive alpha, and in the case of LCH, some strange combination of the other channels seems to drive it. It's possible that there's some property of these color spaces that I don't understand - but it looks to me like a bug.