Well, Bella,
my boyfriend doesn't like cleavage, for one. As Francis said, some men prefer seperated . . .
Mr Cypher thinks (I infer) that since cleavage is pretty much just the result of being packed into a bra and pushed up and squeezed in, it's not the natural look of breasts, and he's the type that prefers the natural state of (most) things . . . And actually I agree with him. I think that space between breasts, below the collarbone, is lovely. I prefer emphasizing that, rather than squashed-in flesh welling up over the blouse.
And about the "right bra can give even an A-cup cleavage"-- well, sure it can, but then you have that effect of looking like a completely different woman when you take the bra off, and who wants that? Rather than faking cleavage, I like to show off the good things about smallness-- high and perky, anyone?