Thanks once again, Graham. This is really helpful.
From what I remember, the cut-off bullseye fairleads are there to hold individual ties in place. You have to untie them and then re-tie them around the main halyard for your chosen reefing position. In the interests of speed, I’ve long since junked this arrangement and now have ties permanently fixed in place on the aft face of the yard, so that the untying step is no longer needed.
As our topmast fairleads are sawn-through, I won't be able to emulate your setup, having the tie left in place. I think just having the ties available to hand will have to do.
Either way, it will be an improvement on my first reefing effort where I unclipped the main halyard and clipped it back on at the reefing point. It worked, but leaves the end of the top mast uncontrolled. A gunter-rig gaffe on my part.
Again in the interests of speed, I’ve placed small Dyneema loops in each cringle, as I found that hooking up to the cringle itself is too fiddly. I have a spring-gated hook on the outhaul. See this post https://www.swallowyachtsassociation.org/smf/index.php/topic,1991.msg13129.html#msg13129.
I tried out a D-bar captive shackle on the outhaul. Quickly realizing (what ought to have been obvious), that the gap in the shackle is too narrow for the outhaul rope to slide unrestricted. Your picture is very useful - I'll be installing the small block to run the rope through. The captive shackle itself works well enough for now, although a clip or snap-shackle would be equally good.
And the soft shackle around the boom will be a worthy addition. Am I right in thinking it doesn't need to be particularly tight and must be loose enough to slide over the mainsheet attachment, to position it further forward on the boom when putting in the second reef?
Same again – Dyneema loops in the luff cringles, at least for the two reefing points. I use an open hook on the downhaul as it is faster to attach and less likely to shake undone than the hook on the outhaul. I’ve modified my downhaul as seen in the attached photo.
The open hook arrangement you demonstrated is exactly what I need. The current shackle I have is a ridiculous arrangement.
One thing I'd like to check - do you hook/shackle your downhaul to the hole in the metal plate at the back of the tabernacle, or onto the spindle that the mast pivots on? Ours is set up to attach to the mast spindle, but I don't like the idea of loading the middle of the bar in case it gets bent, which will unleash a world of nuisance.