The TAKAHASHI METHOD seems to be to talk as fast as you can and to rub it in for those who can't understand you by showing slides with only KEYWORDS from the talk as large as you can project them. You can read my lips if you can read LARGE FONTS, so to speak.
That's a JOKE for second language speakers, who know the importance of having slides for a a talk. In fact the Takahashi method, as well as being a humorous method, seems well suited for LIGHTNING TALKS, where the speaker has come to brain dump but the audience has the brain capacity to absorb more by looking at a poster.
Takahashi http://rubycolor.org/takahashi/takahashi/img0.html sees the characteristics as:
a. VISIBLE to the people at the back. Better than for someone to tell you, 'Your presentation was great but only the people at the front could see,' is to hear, 'Your presentation was ordinary, but everyone understood it!' I guess that one doesn't translate so well.
b. For the presenter, keywords are POINTERS to appropriate content, helping them determine what their point is at each point in the talk when writing it or delivering it.
c. Because there are many slides, one for each couple of sentences perhaps, it makes it EASY-TO-DELIVER by requiring the presenter to decide what to say in a lot of detail before delivering the talk. This makes it good for people who suffer from stage fright.
d. Because there is little information on the screen it helps the listeners CONCENTRATE on what is being said, rather than on trying to read the slides.
Reading the slides, rather than listening to the presenter, can be the first step in not hearing, or not understanding, something.
I may have MISCHARACTERIZED what is on the screen by saying just keywords appear. Takahashi seems to include whole noun phrases in his slides. HEADLINE-type sentences is how a Wikipedia entry characterized them, I think.