Saying that dry-hopping only gives aroma and no flavor is like saying that you can smell peeling an orange, but you can't taste the orange when you bite into it. Dry hopping leaves behind oils and terpenes that are otherwise burned off during the hop boil. These oils and terpenes contribute just as much flavor as they do aroma. Yes, you will taste the hops, for sure. A 5-20 minute boil would infuse these flavors into the beer even more than if just dry-hopping, but after 20+ minutes of heat contact, these volatile oils and terpenes burn off, leaving behind the acids that cause bitterness. While dry-hopping is primarily for aroma - because the terpenes and oils are completely intact since they had no contact with heat - don't be fooled into thinking those oils and terpenes have no flavor, too. Of course, it also depends on other variables such as hop strain, gravity, malts, dry-hopping time, etc.