Let´s say I make the letters A-B-C as a Photoshop file with tranparent background, and I want the letters to fade up one by one next to eachother. If I lay A on layer 1, and A-Bb on layer 2, then the A will dip darker in the middle of the crossfade. I can fix that by putting A in layer 2, and fade up A-B on layer 1, but that is not an ideal solution, as you´ll soon run out of layers if you have more than a few letters.

This can be worked around by changing files and snapping with a bunch of extra ques, but is there a way without workarounds? Simply fade something up on top of itself (on a higher layer) without the brightness dimming down in the middle?