Hapkido was developed to serve the noble class. At the highest levels of hapkido the person shouldn't touch his attacker with the palm of his hand. That is why grappling and traditional hapkido cannot be taught together. Hapkido is about grace and technique.
I have gone full on with hapkido. It is rare to see since normally hapkido full on is just incorporated into a sparring fight. However, at full speed it probably looks like a cross between two spinning people and a cat fight. Its alot of fun at full speed but dangerous because if you don't think you have a proper lock you will just push harder and that can get painful.