Quite a few thoughts in return so apologies for lengthy post:
(To note my set-up is for a combo' Roe deer/rabbit fence. I should also clarify that my earlier remark about durability referred only to my modifications to the “system”!)
Firstly: Foobar, have you considered drilling the “stay-fast” strainer post to take hinge pins? I'm wondering whether might be OK with a light-weight gate !? Also, a ground anchor might counter the sideways shift of weight on the strainer post as the gate swings open. (That said, I note DartmoorLiz's thoughts on the matter.) Also, I'm sure I've seen pics of “stay-fast” corners and/or 2-way intermediate bracing struts at various horizontal angles, but I have no experience of the “stay-fast” set-up so I imagine you have found limits wrt your needs.
Yeah, I'm also thinking Clipex is great! For ends, I'm using beefy posts with the added bracket to take a bracing strut. For corners; 2 beefy posts can, of course, be used instead of a “stay-fast” corner set-up. (Not cheap, but I calculate it is cheaper than a full “stay-fast” corner. However, I imagine rather more fiddly/time consuming if using stock-fence mesh.)
I am going to trial use of a single beefy corner-post with a brace bisecting the angle when my new Clipex order arrives. (Umm! – not really that keen on the idea, BUT will be very cost effective IF it works – am looking forward to seeing how it goes).
While the beefy bracket is designed to take a stay-fast strut, I've concocted my own bracing struts using scaffold tube and fixtures to form a floating brace. (Pic attached)
Having very rocky ground in places, I use a 40mm auger first so that I know the posts (beefy posts in particular) can be fully driven “manually” without hindrance. Proved particularly useful today on a critical corner – had to auger half a dozen holes before finding the sweet spot in between the rocks. (Have used auger also for a few non-beefy posts, but they were then almost too easy to drive! We shall see how they fare over time!)
As I'm not using stock netting, I won't comment on strain first or after.