Although it worked, there were significant disadvantages to Donald's system.  Because the sheets were eased so that the leech of the sails were forward of the luffs, he could not sheet the sails back in without putting huge compression loads on the battens and risking breakage.  It was easy enough to round up and spill the wind from the sails when both sails were on the same tack, if he wanted to change course or reef, but when the boat was wing and wing, he had to gybe one of the sails first.  He had several hairy experiences during squalls when he had to gybe with the sheets slack, including one monumental fan up.

The traditional method for sheeting the staysail to the tiller involves running on a broad reach, not sailing wing and wing, taking the sheet to the windward side of the tiller and counterbalancing it with shockcord etc.  This may work on a junk ketch or schooner.  On a junk sloop, I think a windvane/automatic pilot may be the only answer, although if anybody has experience to the contrary, I am keen to hear it.

Steering on passage is against my religion - singlehanders have enough work to do, and anyway I am born lazy - so self steering is vital.  Arion has a very robust home-made windvane, based on the system Blondie fitted to the Hiscock's Wanderer 111.  The vane is offset on its own mount on the transom and is linked into a trim tab, or servo rudder, on the trailing edge of the rudder.  I can also link a small tillerpilot (autopilot) into the trim tab, which works better than the vane in light, fluky winds or light following winds.  If the wind is 10 - 12 knots or better and steady, the mechanical windvane works perfectly.  It is an extremely robust system that is cheap to build and easy to repair.

From my experience with junk rig, the boats are easy to balance and the default mode seems to be to stay on course.  (I now anticipate a heap of postings telling me how everybody else finds their boat misbehaves and wanders erratically all over the ocean.)  I think with a multi-masted rig, it would be odds on for sheet to tiller to work.  And as your self-steering gear might be wiped out in an accident, it's worth planning to incorporate such a system if you can.

Re Aries, Fleming, Cape Horn and all the other expensive gears: make your own.  Why spend so much money unnecessarily? 

Bill Belcher's book is hard to find and expensive and for some reason, the company here that occasionally publishes a new edition, won't print any more at present.  But if they do, I shall tell you all so that you can buy a copy for yourself.

Thanks for the reply, I hadn't downloaded the latest magazine when I posted that, I just read the article about Eric the Red. It sounds like his experience with sheet to tiller steering was much like mine with the gaff cutter. Most of the time it worked beautifully, but I couldn't steer any course I wanted, and in higher winds with shortened sail it became less reliable. On offshore passages when I had a whole ocean to play in it didn't matter that I couldn't steer exactly the course I wanted, twenty or so degrees was close enough and I would change tacks once in a while to stay close to my intended track. On coastal passages that's generally not practical so I either used a tillerpilot or the Aries windvane. I'm starting work on my deck hardware preparing for the arrival of my new masts and thinking about how to arrange things for sheet to tiller, or whether to bother with that at all. The arrangement I had was very improvised and a bit Rube Goldbergish, but it worked. So much better to plan for the sheet to tiller option when you're fitting out and to set things up with that in mind.

I couldn't find anything on the subject of sheet to tiller self steering on junk rigs, hope I'm not repeating something that has been discussed elsewhere. I'm converting my gaff cutter to a 3 masted junk. With my old rig I did probably 95% of my sailing with sheet to tiller, when it works it's a thing of beauty that involves no extra gear, consumes no power, and there's almost nothing to go wrong with it because it's just a couple of blocks and some rope. The new rig will have a forward canted mast at the bow, a mainsail and a small mizzen. I should be able to balance the boat on any point of sail, but I'm wondering if sheet to tiller will be practical on a junk rig. I do have a Monitor vane and I'm confident it will steer well in heavy weather, I had an Aries before that worked superbly in those conditions but not so well in lighter winds, I expect the Monitor to be similar.