As you read, keep in mind that the material is early work, but still relevant. It's the material that laid some of the groundwork for my book and the things I'm playing with now.
The thing I've had the most success with is using certain kinds of virtual reality to fool the mind. It seems that when the mind has a convincing enough substitute the boundaries suddenly get quite a bit softer. It's a straight-up brain hack.
Repeatability is proving to be a booger, so "packaging" specific workable techniques is really tough.
I've had my share of messy experiences, where I've had to scramble to get Pandora's Box closed again, so I know how that goes.
Repeatability, safety and stability are elusive here (maybe even impossible) so I'm always looking for slower, gentler approaches. The results are less dramatic but there are fewer bad accidents that way.