Interactive Table of Contents question

My latest offering features an interactive Table of Contents. The body of the story is preceded by a column of jump-links that allows the reader to jump to a particular chapter. I've pretty much decided that on longer works (in my mind that means >20K words) that rather than posting as a serial I'll provide this kind of means for the reader to read part of the story, leave and come back later and be able to jump to where they left off.

It does take quite a bit of time and effort to set up the anchors and then the jump-links when formatting. The more chapters, the more time and effort.

My question is, is anyone using it? I realize it's not seen often and may be a foreign concept. But I feel a sense of accomplishment when it's complete.

Your feedback on this is greatly appreciated.