I am building up an old bike for the lady. she enjoys cloth + shellac and I'll be using simple black cat eye tape with clear shellac flakes & alcohol. I plan on wrapping & coating over the weekend.

One idea that she had was adding a small amount of fine silver glitter to the shellac for an extra pop. she figures it will be unique and the glitter will go well with the polished/chrome components. she figures just a little will be better than alot of glitter -- it would just be subtle hint of sparkle. The concept is not unlike adding sparkles to wet paint like seen in Japanese Keirin track bikes.

I am not so sure -- the glitter will rub off or clot up into glittery balls, right? I think the last thing you'd want is glitter rubbing off onto your hands and then getting it stuck in your eye. But then again, it's shellac -- the glitter should stay with the shellac. And the shellac aint going anywhere, for the most part.

Should I just nix this idea or should I go with it? She, of course, has the final vote, but I figure I should consider an outside opinion.

Wrap an extra spot on the bar, mix up just a little with glitter, and try it & see?

I think it could work but I'd do this: hand apply the glitter (and use the smallest flake size you can buy) to the first coat of shellac, do it while the shellac is still tacky. Then "entrap" the glitter with all of the many coats you will apply to the tape. You (or she) will have to keep an eye on the wear of the shellac and re-apply fresh as it wears away or glitter could end up on her hands...and elsewhere.

glitter = perfect [early] Christmas present

If you go to a good art supply store, you can find "glitter" in all sorts of colors and sizes ranging down to a fine powder. Have some fun with it and make her happy.

My first wife used to wear lots of glitter makeup.
I was about 8 coats of varnish into this top dollar Chris Craft restoration for a client you've all heard of when I noticed a speck of red glitter about 5 coats down.
I bet it's still there.