No worries. Glad to help
For the record Iv'e never added it last 15 minutes, just start of boil. It turned out great.
Like stated in the other post it will impart a dryer beer and the sugars will ferment out. You'll still get some flavor depending how long you boil it for. Depending on what your making i wouldn't add more than a Pound, but experiment. To get that sweet flavor your looking for I'd go with specialty grains. But thats just me.