I'd make a bigger bet the freshman would miss the cap on the tail.

If you have a chance to run a sim I'd like to see the difference in AC performance with and without the bulk connected. I don't remember it being that much. The biggest advantage I've seen is increased common mode range.

You can also tie the bulk to a "dummy" diff pair tail in parallel with the main pair, or a source follower tied to inp if yo want the best of both worlds.