I think any instructor can only instruct what he knows. If spirituality is an important thing to him (like it was to Ueshiba M.), then it will appear in everything he does, including his instruction.
To assume that training in Aikido "should" leave one with some spiritual or philosophical insights is like saying that going to Church "will" get you saved. The result has much more to do with you than the person at the front of the room imo.
Just my thoughts.