I agree with Apple. In the case of the Roth hit, Rocco didn't NEED to go himself (he was a capo so he certainly had people under him). He CHOSE to go himself probably because a) he wanted to show his loyalty (this goes back to the Neri vs. Rocco subtheme) and b) Figured he had the best chance of getting close enough to Roth. If he got killed along the way, then so be it.

With Luchessi, I believe that WAS a suicide mission, and Calo deliberately did it to avenge Don Tomassino. Calo probably didn't care if he got killed or not; all he wanted was vengeance ("Blood cries for blood" or whatever he said).