experience and practice is what really matters in this sort of situation...
Sure everyone has, or has seen a tank that is built with very thin glass and thin seams... Whoever built that tank; well lets just say it wasn't their first attempt...
Get scrap glass, gain experience by making perfectly square clean seams and dimensions with RTV -108/103 silicone which starts skinning in 5 minutes or less...
dont order all of your expensive glass and use your show tank as the guinea pig.
You can only learn so much from research, getting hands on and practicing is the only way to learn what actually works, and more specifically what works for you and you skills/style/assembly process/ patience...
Good luck, PM me if you need a helping hand. I am in the process of starting a custom glass aquarium fabrication business. I already know alot, but with each build i gain further insight. No price tag, but pizza and beer at the end of the job is always appreciated.......