The Cleric is the manual. The Paladin is troubleshooting.
Clerics tell you what is bad and tells you how to stop it (vaccine). Paladins prevent the bad from getting you should you be unable to stop it (cure).
No, from a PCs point of view, they're quite different, they do different things. The Paladin does not play the same as the Cleric, this is all they need to exist. It's not like the 4e team was timid in their cow killing.The cleric is the primary manifestation of divine power-a sacred person.
The paladin is a highly specific holy warrior type that essentially falls within the same niche but is in the 4e PHB because it was in the last PHB-a sacred cow.
If there was one sacred cow of a class I wanted slaughtered for 4e, it was the paladin.
Classes are a game construct, they don't do anything in the world.
I've been pushing this since 1e. I set up an organization of "Rangers" that dealt with supernatural threats. They were primarily martial, but had a strong contingent of wizards. It was pretty funny the first time I got to say "the Ranger casts disintegrate."I'm starting to lean this way to be honest.