it takes me to the overview help which works, BUT clicking any of the links on that page gets you
Guide views_extjscomp was not found. Maybe it was renamed to something else? Or maybe it has passed away permanently to the 404 land? This would be sad. Hopefully it's just a bug in our side. Report it to Sencha Forum if you feel so. Sorry for all this
The link to the sencha forum is to a closed thread. The fix is to change the URL to http://docs.sencha.com/architect/2-0/#!/guide and then it works, but someone getting a marketing email might just think your product has poor quality. Either way, no one bothered to test this stuff before it was widely distributed.