So the hirarchy are from global dimension, for example : divisi and department. And the shortcut dimension could be salesperson group, customergroup, area. And then you can use them in the analysis by dimension feature like sales, purchase and financial. Before use the dimension (either short cut or global), you must set the analysis view.
It is not necessary to set up an anlaysis view prior to using dimensions. The analysis view van be updated going backwards specifying a specific date or range. It is however necessary that the dimensions have been set on the posted transactions. In some cases its better and preferred to not auto update the analysis view to speed the posting routines especially if you have a lot of views. You can manually update them when you need the information (monthly,quarter, etc.).
I think part of the confusion here is with what a shortcut dimension is. And as stated above it is a quick way to enter the dimension values without having to click a button and go into the dimension form and enter them. It has nothing to do with how many dimensions you can have. You are just entering those as the most common dimensions to give the user a faster input method.
You can always change the order or selection of the shorcuts in the future if you find that you need to. This has no impact on the data, but be cautious, if you change Global 1 and 2 (Shortcut 1 and 2) this does impact the posted transactions.
You are best to get Global 1 and 2 right at the begining. These are the primary way that you want to segment your G/L account no.