Good speed reading courses and books not only teach you how to skim faster and not to subvocalize but how to comprehend and learn better.
For example in Paul R. Scheele's book he teaches you how to start on a book:
read the table of contents,
then read the headlines through the book,
then speed read the book and then try to probe your comprehension, ask questions etc.
The table of contents and the probing is the most important. Teaches you recursive learning, when you first build a foundation then you fill out the details.