porgress up and down

I have recently been involved in a serious and important discussion around how to assess experiential learning and match it with taught stuff. It is like copmparing apples with oranges, BUT if you shift up a conceptual level they are "fruit".
SO how do we recognise Fruit? can we allow distinctive varietal differences? or do we have a must have and might have list?
are the critical definitions of fruit sufficient? or do we need a flavour of each specialty (major) fruit?
quite a challenge really, AND very important when prior/exepriential learning is presented to assess.
I'd love some comments on this from you all.