Tony Buzan in his book
Use Your Memory writes that most people try to learn line by line. However according to him famous actors and actreses use the reverse P172
quote:
"In this system the material to be remembered is read and reread quickly (see Speed (and Range) Reading)and with understanding over a period of four day, approximately five to 10 times per day.
He goes on to say that after the 20 time you find that you are able to recall the information without looking at the text. Especially if you use imagination to help you understand. Additionally he says this system can be improved by using a image and link system.
He seems to suggest that part of the link system should be the last words from the previous speaker and the first words of the next speaker. So you could be looking at applying your ABC lists in this way.
You might want to get a hold of the book and check pages 172 and 173 (a quick read in the bookstore the subheading is Dramatic Parts and Poems near the end of the book) 
The rest of the book explains other link systems and memory techniques.
Alex
