Steve I understand when working with pencil, charcoal, etc. that you 'erase' to enter highlights. I've used the technique for more than 50 years.

I don't see how it applies to using vectors within a computer application. You don't need to erase to create highlights, you can add a highlight shape, subtract a shape to create a highlight and several other variations which can be used as easily or more so than an eraser tool. It does not seem logical to me to need or want an eraser when using vectors.