Although I really like a lot of what I've seen of 4th edition, I agree that these two disconnected effects of one ability are something that I rather dislike.
However, I also see why they made them. There used to be dozens, scores, perhaps hundreds of discussions over on the Wizards boards about how people hated playing clerics, and to a lesser extent paladins, because they buffed and healed INSTEAD of whacking things.
Now they're giving the people exactly what they were asking for -- a way to participate in combat every round and still give some advantage to another member of the party.
I can understand why they did it, and it's certainly not something that's going to change my mind about my preorder. I just wish that there was some way to achieve a balance between having the paladins and clerics fight and still be useful to their comrades, and the mental 'disconnect' of the abilities.
Still, it should be possible to fluff it as the "Pelor, protect my comrade while I cannot, because I am smiting thy foes" syndrom.