I like your view point, however I think he can revive anyone he wants; despite if they were killed by him or one of his jutsus. For instance when he brought back the weird robot pein body (the one that Chogi and his Dad smashed with their giant fists) it wasn't killed by his own jutsu. I believe that is more related to time. As long as too much time had not passed from when someone had died he can still bring them back.
That's why I believe that by the time he figured out he could do this it had been far too late to revive Yahiko. That's also why Jiraiya's not gonna come back
