Here's what I don't understand...why announce that you will pray for someone or ask if you can? If you feel like you need to, or that you should, pray for someone then do that. Does making an announcement that you will pray or want to pray make said prayer more powerful? If you want to pray - pray. Announcing your intentions may make you feel bigger and better but that sort of takes away from the selflessness of it.
“If you are the smartest person in the room, then you are in the wrong room.” — Confucius