I'm an idiot.
I've not been thinking and your simplified idea made me stop and think. Thank you.
We have a Seldon boom. The Seldon boom has a sailtrack built into both the top and bottom. Once we have finished with the new lazy jacks and sail ties the only thing under our boom will be the vang/preventer attachment point. If I go back to a two piece cover it can be suspended on the centre line with a couple of hooks to fittings in the lower boom track. Aft awning goes to the vang attachment point. F'ward goes from there. Allow some slots for the sail cover straps to drop through and bob's your uncle.
edit.....Cameron......our new lazy jacks have four legs. That would mean we'd need a five (or ten) piece awning......
Hi A, on your first point... nah, won't go there.
But on the second: My original "pre-edited" thought was that you could hang the awning from a line under the boom, supported by saddles or slides at intervals, but then it occurred to me that it is much simpler than that.
Your lazy jacks have four legs?? That's fine. Nope - you don't need a multi-piece awning. I was down at the boat today and did think of taking a pic of ours, but what I wanted to show I couldn't zoom in close enough. I'm hopeless at MS Paint, so bear with me whilst I try to detail my suggestion above:
Under this scenario, looking down from the top of the mast, the awning does not cover the boom or touch the lazy jacks, but sits parallel to it and hanging from it. Assume two awnings, one port, one starboard (the blue shapes). The two awnings clip together (black squares) using the webbing straps (red) over
the boom and between the lazy-jacks. You make the straps as long as you need to get the awnings sitting level either side of the boom with a gap wide enough to get your hand through. Basically, 6 clips and she's on and tight. Very easy..
If you've got covers or high sides (or something like that) that with no way to pass a strap across the boom above, you could always revert to clipping the cover across and over a line run on a half-dozen slides along the track under the boom. Whatever works for you.
If you want to divide either side in half, use the same system, but with the webbing sewn in 2" or so back from the edge of the join underneath the awning parts so that there's a slight overlap whne the pieces are clipped together. Four clips each side of the boat would be enough.
Make sense now?? I hope this helps.