I've heard that one before and haven't bought it. The fact remains that he is still, for that entire time, an all-powerful divine being, even if he is in human form. The amount of suffering that God could easily endure surely must be much less than, say, a person voluntarily subjecting himself to getting a tattoo.
But if He's omnipotent, He can choose to endure that amount of suffering if He chooses. Being omnipotent means He's capable of doing anything, right? It's completely voluntary on His part. And who said He "easily" endured it? He is all-powerful and divine. But at that very time, He Himself admitted that if He chose, He could just say the word and the angels from heaven would come down and slaughter His captors. But He chose not to. He could have chosen to end His suffering at any time. But He did not.
God, in His divine nature, does not suffer; He dwells in bliss. That is why He became Man, in Christ: Christ is the compassion of God.