That hypothetical in and of itself is a change in preference.Prov. 6:16 says, "there are 6 things the Lord hates, seven that are detestable to him" and the 19th verse says one of these is, "...a false witness who pours out lies and a man who stirs up dissension among brothers."
I can change my preference from blonds to brunettes but I can not change which sex I am attracted to and neither can anyone else RR.
In the same way a non-smoker can smoke a cigarette a heterosexual can have sex with a homosexual but it does not mean he has changed his sexual preferences.
A straight man cannot have gay sex and still call himself straight.
He's straight but CHOSE to have gay sex.
That IS choice.
That tells you his sexual preferences are just that - preferences, not innate and surely not an orientation.