Basically agree: "romantic" is simply a flavor of sexuality-- one form that it can take. But it's still sexuality. Just as much as being attracted to someone in a purely physical way is. And the whole thing comes down to sexual orientation. Always.

"Romantic", in this context, just means that the emotional component of sexual attraction is especially pronounced. Nothing wrong with that, but it's not a separate thing. And there's no need for it to be.

So, no, I don't think that "romantic attraction" can be "split" from "sexual attraction". Pretty much the sole legitimate use of homoromantic/heteroromantic (imo) is for some bisexuals, and then only in a very qualified, restricted way. Since we essentially have two separate (if intersecting at various points) types of attraction, and they can operate in quite different ways, it's possible for us to have a stronger emotional attraction to one sex than the other. Not that it's necessarily so simple even in those cases (speaking from personal experience here)... but this seems like one example of how our sexuality is distinct from that of gay and straight people. However, note that, even here, it's still fundamentally about sexuality. Just a matter of how that sexuality is interpreted/experienced by the individual to whom it belongs.