Separating RGB from OSC vs HSL color modification

Hello everyone, and APP developers,

I searched for the direct answer to the following but did not find one easily. 

To control the relative contribution of colors (RGB only, no filters or bandpasses), are these methods identical or different?

1) Calibrate, stack and process in APP as normal, and then use HSL color modification to selectively increase saturation of each R, G and B from the RGB images (not split).

2) Split the RGB channels from OSC camera fits, modify the colors individually and then recombine.

Is using HSL on RGB images identical to modifying the R, G and B split channels followed by recombination? Or does one method give greater control over each color than the other?

I am curious about adding a superluminance or synthetic luminance to RGB images, without first splitting the RGB into R, G and B to make LRBG using the combine tool.

Again, this is only for OSC color images without any filters.

Best wishes, Col