I think that depends on your own personal definitions of sexuality. I spent some time reading the book
Nobody Passes by Matt Sycamore earlier this year which addresses the very nature of that statement. Placing someone into a "category" more often than not does a disservice to themselves, and their way of life. Granted, we as human beings prefer to categorize things in order to make our lives easier, but I'm of the mindset that sexuality is something that cannot be easily placed into anything. You like what you like, and that may include some things in regards to your own sex, or some other "deviance" that others may find strange, or downright horrifying. Trying to conform to a single definition for some of these people who may identify as LGBT may be extremely difficult, and in some cases, may be downright impossible. Which of course limits their own acceptance not only with heterosexuals, but with the gay communities as well.