I call Ingeborg's rig huge, in comparison to Jester's, not because of mast height but in relation to sail area.  Jester's rig has quite a high-aspect ratio.  This is not a criticism, as I am an advocate of big rigs, regardless of whether the vessel is a junk or not.  As Bernard Moitessier said, you can always reef but once all the sail is fully up, that's it.  As Arne points out, the junk rig is so easy to reef that this concept is even more attractive.  It is especially important for junk rigs because the extra sail area acts as your light-weather canvas since one cannot set genoas and kites.

In relation to downwind sailing - I am sure Jester's rig can be driven harder downwind than Ingeborg's (or Arion's) but I don't really see this as being much of an advantage.  The rig is so powerful off the wind that you don't need much sail area.  I often sail Arion downwind with just the three fanned top panels in fresh winds and lope along at 4-5 knots with no weather helm, no stress on the rig or, most importantly, on the skipper!

To windward I carry a lot more sail for a given wind strength.  With the sheet eased, the boat hardly heels and remains balanced.  The top three panels, as Arne points out, offer a superbly efficient shape for heavy weather sailing.  I am willing to stick my neck out and declare that the Hasler/Mcleod sailplan, modified by Arne's transitional panel, is the best junk rig configuration developed so far, with or without camber.

So I think a Folkboat with this rig and a modest amount of camber would make a very good showing in the Jester challenge or any other ocean passage.  I am sympathetic with Arne's position on sailing Ingeborg across the ocean, however, since my own health is also becoming increasingly fragile.  I have just sailed Arion 1200 miles up the east coast of Australia and am still dreaming of ocean passages but there are days when I wonder if I will still be sailing next year.  What I do know is that my wonderful, easy to reef junk rig is likely to keep me sailing longer than any other rig would.

This topic raises a number of sub topics; camber, rig size, radical versus conservative, fit for offshore or not, etc.

Rig size first.
I have PJR and a calculator by my side, right now. I find that Jester’s mast height is about 10.3m above the water line. Ingeborg’s mast is only about 9.6m tall (above wl.). Still, one seems to regard Ingeborg’s rig to be the ‘huge’ one.

I wonder when it will sink in that the JR can be reefed quite easily: Now, I haven’t been out in a ‘three-panel wind’ in Ingeborg yet, but in my much tippier Frøken Sørensen, a brisk F5 is enough to call for three panels when I am alone on board. My experience is that those three top panels are remarkably efficient to windward. No creases and no fluttering leech. The lee topping lift limits the twist to just the right one to adds a bit camber to the sail. The topping lift also seems to ease the load on the battens. I once was forced to reef FS to only two panels and even with this handkerchief (6sqm) I was able to tack her, although the tacking angle was quite wide. I also remember that Johanna was happy under three panels in a blow.

Jester’s rig has one big advantage: Her high boom and short chord sail (max 3.43m) ensures easy downwind handling. The broader low-balance sails I usually design will require a good rudder and powerful self-steering. I have started to compare my sails’ chord with the waterline of the boats. The present rig of Ingeborg has a chord/waterline ratio of 0.80, which I think is on the edge of being too high. If I were to design an offshore sail for her (same mast), I would reduce the battens from 4.9 to 4.7m and make the sail just a bit taller. That would shave off less than a square meter.

As for Ingeborg versus Jester in the 2018 Jester challenge: No way, at least with me on board! My slightly fragile carcass is not fit for solo offshore challenges. Right now I have been grounded  for over a week  - and will so be for the next few ones  -   with a cracked chest bone.
Only when I laugh...

Cheers, Arne

PS: Jester’s rig was radical enough when it was designed, (just as the first T-Ford was), but it is sad that Jester II got a holy grail status, so any research and development work on it was out of the question.

... so how about it, then, Arne? Ingeborg vs Jester, head-to-head in the 2018 Jester challenge?