....That isn't really the issue. Having more than one element representing very similar elements on the periodic table doesn't look right in-game. Boyle's Water reaction was added so that there would still be some way to perform this reaction.
This is because, Hydrogen as an element is boring no matter what it does. If it exists only for additional neighbor reactions, then there's no point in putting it up. ^^; Each element must do something no other element can emulate, or it is wasting precious space and CPU cycles.