That is not how I read
that post by Chas521/Rafke.
Clearly, as said in
that post and from my experience,
sys.txt settings override every other setting, also those in igo.ini.
You are possibly confused because that post is in 2 parts.
In the first part is described where iGO looks for a certain file.
example : the loadings screen: first iGo looks in the root, then in skin.zip, then in branding.zip, then in data.zip. The first loading screen iGO finds, it uses to start up. Since it's not in the root, it is in the skin or in the branding.zip. Simple. Install a skin (diMKA is a good choice for this) and look for yourself.
In the second part is described where igo looks for settings. Sys.txt comes first and overrides every other setting that follows.
A good tip is to add in sys.txt the [device] header and the name of your device if available in data.zip/config/devices. This way, sys.txt calls preset settings.