No, you age barley wines, not IIPA. Your homebrew shop guy is mistaken. Unfortunately you will find most of them are about many things concerning brewing.
My suggestion is to sub out at least 5% sugar for some of your extract and keep the crystal malts to a minimum. You want this beer fairly dry to show case the hops. Too sweet and the hops will clash. These beers are meant to specifically showcase the hops. That is why they should be dry and fresh.