From what this function sounds like, it is meant to "retain image sizing". Which means that you will retain the ORIGINAL image size, not provide an ADJUSTED image size.

The whole purpose of the https://img1.steemit(dot)com/LxW/ function in front of an image was to adjust the display of an image on a post. I believe the original image would still retain it's original size. 

If anything, 1723 COUNTERS the https://img1.steemit(dot)com/LxW/ function by ALWAYS forcing the ORIGINAL image size. At least that's what I'm gathering from the function based on what I have read.