Undercutting will exist as long as SE does not implement TAX on listing items on the MB. Now tax is done only when item is sold. TERA had a tax system when u put item on auction 5% and another tax when item was sold (exist now). A tax on listing items on MB will greatly decrease undercutting as u will loose at lot of gold every time price is adjusted.

I'm on phone now or would make an individual topic for discussion.