Honestly, pushup bras are no different than wearing makeup, dying your hair, wearing flattering clothes or wearing spanx.
All of them are designed to make yourself look a little better than you really are. If you are an A cup, it won't make you look like you have a D cup. Just like your standard makeup job won't make an average girl look like a MODEL (unless that girl is spending HOURS doing it which is a whole different story). Spanx won't take you from a size 14 to a size 6- it just wont.
I wouldn't consider it lying at all and from what I've noticed, most guys are so into the thought of having sex that by the time its coming off they don't care.
If a guy is THAT hurt by the decrease in your bust size, chances are he was only in it for the physical anyways.
I couldn't care less what cup size she is. Once she attracts me whether with fake breasts, high heels, or by stuffing her bra, I'm hooked and then will follow through. Of course, if she turns our to be a he or something ridiculous like that, then all bets are off.
I think we need to give guys more credit.They have seen enough Victoria Secret Catalogues and fashion shows to know about bras that enhance a bust. Honestly,i don't think they give a rats arse.If he happens to make it to the point whereas he is actually able to remove your bra,i doubt that he would make a fuss right then and there about your actual size.In fact,i would say he could care less...he has other things on his mind.
Many push-up bras do NOT increase up to 2 cup sizes. It's just those stupid bras at Victoria's Secret that do. The point of those type of push-up bras ARE to increase bust size. Victoria's Secret think all women want to be a size D+.