WARNING: Some people got freaked out by the awesomeness of my dumb questions and incorrect language. So please ignore the little mistakes, missing knowledge, be sure that I´ve googled my questions before with no results and, please, answer in a gentle way. Thanks.
As long as I know a Group Instance is an exact copy - not duplication - of another object which uses up less memory because Blender doesn´t have to read he geometry data twice.
But if a Group Instance copies the exact geometry data, why can´t I add a particle system? A particle system (hair) just needs the geometry, not the object itself for producing an hair system (not talking about hair modifier!!).
Is there any way to add a particle system without adding it to the original object?
Thanks all of you beforehand, and I wish you a happy new year!