Jasper - there is a right and wrong way to fit the boards.... most are bought as consumable boards and installed however the chippy, contractor, developer, main contractor, labourer wants - then rendered on......
You have to apply the correct render to a board - basecoat and mesh, then a finish coat! Render system suppliers all have approved boards (not all the same boards!)
The render thickness and type is defined by the render system supplier you use, but some boards can take thicker and heavier finishes (it is more to do with weight, than thickness).
Consideration has to be taken to the expected shrinkage of the TF, and allowances and movement joints installed to suit.
I suspect that the project you are referring to, has butted boards and then a scratch directly applied..... the TF shrinks and the boards rub and move, the cracks come through on the joints.... then depending on the render and the location, water gets behind and it starts to delaminate!
I will be more than happy to assist and advise further if you like (or just send you info in the form of an E Mail).....
Richard Lord -
rlord@knauf.co.uk - 07918766577 - Knauf Drywall - Knauf Aquapanel Exterior Specification Manager.