Yeah i would say Neville’s way is logical. after going into my heart so many times, you can just tell if someone is really in there heart or not. when your in your heart (5th dimension), there is only light. no darkness. you can’t even cast a shadow. but when your in your brain (4th dimension and lower) there is duality and polarization. the simple act of trying to avoid negative thoughts is a dead give away that the person is not in there heart.
also, when they say “be in your heart” it’s not simple putting your awareness on your heart or heart chakra. its actually moving within your body into your physical heart. like your body is a hollow temple and you are a little spirit marble and you move into your physical heart. also the akashic records are in the heart. since all hearts are one.
here’s a screenshot from The Ancient Secret of the Flower of life book 2. that circle underneath the head is exactly where the lower heart chakra is.