As you consider these ideas, remember that hook-in failures are not 1-in-100, or even 1-in-1000, events; they are extremely rare events. So all "solutions" proposed here are attempting to make an extremely rare event even rarer, which is a very difficult task.
At the risk of editorializing, here are the points that I felt were the most uniformly agreed-upon during our discussion:
[Of course, many of our members have been using such checklists (both mental and printed) for years. The consensus of the meeting was that both the CHGPA BOD and the membership should take a more active role in promoting the use of a checklist with those pilots who do not. As more pilots participate, the checklist becomes standard procedure, and hopefully the risk of hook-in failure decreases.]
Did you forget to bolt a basetube/downtube junction? Perhaps you're struggling to tension the sail and cannot because a lower wire got wrapped around the control frame somehow? Did you just climb into your harness without putting on your jacket, so now you have to struggle back out and start all over? Maybe all three of these things just happened to you?
If you find yourself forgetting things during your setup procedures, this can be a vital clue that you are not as mentally sharp as usual. Pay attention to such lapses and step away from what you are doing in order to regain your focus. If you then find that things still aren't clicking the way they should, perhaps you shouldn't be flying today, eh?
Be cognizant of your mental state!
The One-Track Mind
Some pilots can be so intent on flying that they seem to forget the fact that years of flying and miles of thermal gains still lie in their future. You know the type: absolutely GOTTA fly, so focussed on conditions/other pilots/whatever that they don't even pay any attention to their wirecrew.
Being focussed is great, but if overdone it might result in important procedures being skipped (ie, the hang-check), and then this mind-set becomes a risk factor.
So try adopting a more laid-back attitude. If you don't get to fly today, well, so what? Fly tomorrow! The sun and the thermals aren't going anywhere...
We all have preferred methods of pre-flighting, approaching launch, running a checklist, and then taking to the air. With time, these methods become second-nature, and require almost no conscious thought.
But suppose something breaks your customary routine: a batten might be discovered to be loose after you've hooked-in; or your radio doesn't work and you have to climb out of your harness to fix it; or you back off of launch because conditions are rowdy, unhook, then forget to hook-in as you rush back to launch during a mellow cycle. The list of potential distractions is as varied as the conditions we fly in and the gear that we carry.
Many pilots agree that the most frequent cause of hook-in failures are distractions like these. So when they occur, try to BE AWARE THAT YOU HAVE BEEN DISTRACTED! Take a moment to acknowledge "hey, I'm breaking my routine and I don't like this! I've got to be doubly careful not to screw something up now...".
Deliberately cultivate those niggling feelings of unease that arise when your routine has been compromised; they give you an additional edge.
The core item of all checklists is, of course, the hang-check. Different pilots will probably have different items on their lists, and their own preferred order. But the important thing is having such a checklist and performing it prior to every launch. If the practice of running a checklist becomes ingrained, then hook-in failure risk will be reduced.
Some pilots have mentioned reluctance to prompt a "sky-god" to run a checklist, especially if they are relatively inexperienced. Please don't let the difference in your experience levels be the cause of a skipped checklist, it benefits both of you! If a pilot gets irritated about your assistance, well hey, explain that a checklist is the protocol around here, that's just the way it is.
Provided that your harness design and the conditions of your launch site permit, this practice can go a long way toward reducing the risk of hook-in failure.
[Ed. note: Hooking my harness to my glider has completely changed the way that I view preparing for flight: I don't "hook-in" at all, I "climb into my glider". Climbing into a harness that's unattached to a glider feels really weird to me now.]
If you will need a wirecrew in order to launch, try to assemble all members of your crew before moving to the launch area. With everyone in one place at one time, it becomes less likely that a member of the crew will simply assume that a hang-check was performed before his or her arrival.
A hookin-check is simply another confirmation that you are indeed attached to your glider. It can be performed by lifting the glider slightly until you feel a tug on your harness mains, by squatting down until you feel a tug, or by looking over your shoulder and visually confirming that your carabiner is attached to the hang strap.
Overkill? Some might think so. But I think an attitude like this tips the odds against the possibility of hook-in failure significantly.
In all likelihood, maybe ten years from now, after the recent incident has faded from everyone's memory and procedures like running launch checklists are so familiar they've become a part of the background, someone will become distracted and fail to hook-in once again.
You may be able to avoid being that someone by adopting several of the techniques described here, by flying with watchful friends, and by paying attention to your mental state as you prepare to fly.
Educational Resources for Hang Gliding