[Greg McKaskle]

Keeping only the green plane will be similar to looking at the world through green tinted glasses, and it will help to ignore purely red and blue objects. What does it do to a white object?

White minus red minus blue is ... Green. So, you can no longer tell white and grays from green. Additionally, what about yellow, or Cyan?

At least in some implementations, HSV is a less expensive conversion than HSL, so you may want to compare their timings.

Greg McKaskle