Possible bug in scaling lightness

[patricknelson]

I found blend.scale() to work in an unexpected way. I'm not sure if I'm simply mistaken or if maybe this is a bug (or something else). For example, I had a fairly dark test color #592e13 which has a lightness of ~24%. When I used blend.scale() to reduce it by 4% (see below) the lightness of the resulting color was ~23% and not the expected ~20%:

@use "path/to/blend" as blend;

$baseColor: #592e13;
@debug blend.lightness($baseColor); // 24.3875424652%

$scaleColor: blend.scale($baseColor, $lightness: -4%);
@debug blend.lightness($scaleColor); // 23.3712907673%

$fromColor: blend.from($baseColor, blend.lightness($baseColor) - 4%, c, h);
@debug blend.lightness($fromColor); // 20.3776211491%

So, it looks like $lightness is being interpreted as the percent of the current color's lightness and not in overall lightness (i.e. relative to 100% lightness). Is this intentional?