@Yale what did you think having done it? - proof of concept is what actually counts.
To be honest it actually makes the stack have a safe feel about it.
The first stack is manageable however when stacking and trying to get the fork out the whole column comes towards you until you shuttle back and forth and the spikes eventually come out and it falls back.
I would be hard pressed to be able to argue it was safely stacked.
The second stepped stack behaved differently in at no point did the bales want to fall towards the loader.
Having seen it work I will be stacking this years straw with steps.
The only difference will be an extra step to go an extra 2 bales high.