francophile 

Here's the deal: It's single-part enamel, which means it takes longer than you may expect to fully harden up, there's (at minimum) a multi-day cure/harden time involved and if you top it with clearcoat, you ideally need to wait days or weeks before doing so, unless you have specific info on that product's topcoat window.

It'll never be as bulletproof as a 2-part paint using a catalyst, and if you come at it too soon (days, sometimes a week or more) after you apply, it will rub away. This is both an advantage (for mistakes) and a disadvantage (takes a while). It really needs to harden before you rub it out, if you plan to. And quality of adherence is highly dependent on your surface prep, whether you give it (or the basecoat/primer, if used) enough tooth to lay into.

There are plenty of products out there other than regular frog tape (or similar) you can use to paint the actual lug and valley, then spray your multiple fine enamel coats, and remove the product. If using tapes, I prefer to pull my mask immediately after the last shot. If using other products, I wait until 2-3 weeks has passed before trying to remove.

I think you can definitely get good results. Paint is ... ultimately you get out of it what you put into it, time included.