Just another data point and an opinion.
The tether seems to work for me and I open and close my tour-pak frequently. I go on many camping trips with the tour-pak stuffed with gear. Over 96K miles on my 2011 and over 60K miles on my previous 2004 Ultra and never had a problem.

 

All good, but my approach was not to see how long I could go without a problem, so now I know I wont have a problem.

 

I'm looking at the Ultra brace and the pics have me wondering. Is this a bolt in replacement? The pics make it look as though it mounts on the left side of the tub. Mine is bolted in on the right side.

 

you do have to drill your tourpack for the install. not very difficult.

 

Tourpac opens right to left - show us a picture of yours bolted on the right side?

 

The retractor is bolted to the tub to the right of center.

 

http://www.eglidegoodies.com/id40.html

Check the link above,,, You will find several pictures, they do have one similar to what you are talking about.

 

If the top gets away from you in wind or with something on the rack chances of that stopping damage is a toss up.

 

Eglide sent me this video.

http://www.eglidegoodies.com/id277.html

 

sure does look like a person could make some brackets for the arm. you could use bolts and nuts instead of having those little studs on the brackets. ok now, i'm on a quest.