dry hopping usually gives you a very strong aroma, and no aroma will be boiled off. thats all i can really give. you can just put them in the secondary, no need for a bag.... no sanitation issues.
when transfering you might want to try to wrap your siphon in some kind of a filter (cheese cloth, paint strainer, etc) so you dont clog it with the whole hops... also whole hops soak up quite a bit of wort but what can ya do.
(dē-fěn'ĭ-strāt') To throw out of a window.