Can someone explain the difference between CAN "GET IT" and CAN COMPREHEND?

The expression 'get it' is slang for 'understand' or 'comprehend' but is used, perhaps, more when someone has worked out the answer to a puzzle or conundrum. Imagine that you have told a joke or said something that appears to be impossible and the person you are speaking to doesn't understand at first but, after thinking about it, works out your clever logic or sees the humour of the joke. When the light finally dawns, they may say "Oh, I get it, now!" It means something more than understanding or comprehension, really: it involves appreciation as well.

Hmm? I don't think "the difference between 'can get it' & 'can comprehend'" has anything to do with right-brain vs. left-. It's like snare-drumming technique: I can 'comprehend' how the diddle should work, but I can't 'get it' until I feel the weight/balance of the drumstick and try it a few times. (in case you don't know, a 'diddle' is how a drummer hits the drum twice or more with just one stroke of the drumstick.)