Yes.
The pilot had I'm sure a perfectly serviceable altimeter with which to tell his altitude. If he was deluded by the glassy surface of the sea, it's because he wasn't maintaining adequate situational awareness.
If he's an instructor, he knew all the mechanisms for ensuring safety when handing control to a student. If he's not an instructor, he shouldn't have handed over control.
A tragic accident, but it's hard to see this as other than the consequences of misjudgement on the part of the pilot.
G