Energy Work

Hello, I want to know what the difference is between working with the upper dantian versus working with the anja (3rd eye/brow) chakra, I know that Bruce always talks about not deliberately filling the upper dantian but rather filling up the lower dantian and in time this will overflow into the middle dantian which in time will overflow into the upper dantian. But still, I'm curious what the difference is between working with the chakra system and working with the dantian system. (this question pertains to developing psychic abilities)

And I have a second question is it true that by working with either one system or working with both systems as it's layed out in 'Astral Dynamics' a person develops psychic abilities?

And if so what are the signs that latent abilities are developing?