uhhhh muscle testing?
im 'flicking' where you make an 'o' with your index finger and thumb. clear yes circle stays complete, clear no circle breaks. and always ask if its in my highest good to know. this method my doctor showed me for discreetly using at school (asking which questions i should study, which ones i can skip, "will this be on the test")
the flicking method is deffinatly one of the hardest to pick up, im not sure why but that reflex area seems to be hypertonic quite often.