Invisible increase - working one more stitch between increases

Pattern that I'm using and strikes me to "work one more stitch between increases on each increase round."

The increases have been a make one below invisible increase. I'm curious if the question just means keep making one below or if I'm supposed to make an extra stitch in addition to the stitch that's one below.

To be clear, I'm not asking how to do an invisible increase, I'm asking what it means to work one more stitch between increases.
I have also included a photo of the pattern.

Thanks!