I ran two training courses this last weekend, something we call 'Cat Chat'. About an hour of me yakking and asking questions, safety issues, history of beach cats, safety instructions, sailing differences between monoslugs and multihulls etc. I also demonstrate rigging, righting, launching etc. All of our students have previously qualified to a minimum of White Sail III, so this is part of our Club's contribution to 'growing' their sailing skills.
Then I took two students out on the modified H16. Winds varied from 8 - 12 knots, and fairly choppy. I handled the sheets while they got used to stalling during a tack, and whipping around on a gybe. The modified mail sail was fine, other than recognizing we will have to install a plate and/or some more reinforcement on the foot of the sail.
On the last run, the wind picked up, and on a screaming reach, we planted a hull, raising the stern up high. I released the main, but was not quick enough to release the traveler as I was busy sliding down the tramp. Good experience for the students, how to recover from a capsize, plus the water was not too cold.
Now this, from Sunday's sailors :
"All, Jim P. and I took the opportunity to take out the modified H16 on Sunday afternoon after John's on shore course. Although at times the winds were on the weak side, they were certainly steady enough to sail and to get a feel for the boat. The main sail held its shape reasonably and seemed secure; however during gusts I did fear a bit for the grommets as they are currently installed. (I agree that the proposed aluminum plate should rectify this).
Overall I think that it sailed quite well, maneuvering easily and predictably. We successfully tacked and gybed several times without difficulty or incident. In fact I don't think that we even stalled once

Further, it seemed stable throughout all points of sail. Having said that, I should admit that I have not sailed an unmodified H16 for some time and cannot be completely sure of the differences in terms of performance.
It is fair to say that I found it quite comfortable to sail without a boom "threatening" on each tack and gybe. Also adding to the comfort, there is slightly better visibility and more room on the tramp.
With the addition of the aluminum plates to reinforce the foot of the sail as proposed, I don't see any issues with this configuration. Further, as has been mentioned previously in this thread, in terms of safety, I would agree that this new configuration, both with and without the extra plate is actually safer than a stock H16. It removes the potential of colliding with a boom either during normal sailing or during a dramatic capsize. Although unlikely after adding the reinforcing plates, I don't think that tearing a mainsail would be a serious safety issue since it should still be possible to sail with the jib if this were to happen. Has anyone tried sailing with just a jib on an H16?"
So far, so good.