Gohan only surpasses Piccolo when he becomes enraged, which only happened when Gohan channeled his Masenko. Aside from that, he couldn't even follow the movements of Yamcha.
Gohan received a temporary burst of power because of the confidence he felt when his father was returning. In no way before or after does he show enough battle to replicate the feat.
Gohan received a temporary burst of power because of the confidence he felt when his father was returning. In no way before or after does he show enough battle to replicate the feat.
His normal power on namek was 1500, so he should be lower than that on earth. Piccolo would at least have trained him enough to utilize the 1307. He does train for a full year.