Marzano and Simms are strong advocates of direct instruction chunked into short, polished, carefully-sequenced segments. The primary function of the Units is to provide mini-lesson ideas that build on one another sequentially. The qualities of whole-group instruction described in Marzano's book match the qualities of a mini-lesson nicely.
The book argues that independent reading is imperative for "self-teaching" -- the development a reader undergoes once they begin connecting sounds to print. The book goes on to say that independent reading is doubly important because English has the richest orthography in the world (various spellings for various sounds). It's impossible to teach orthography directly in English, as there are far too many letter-sound relationships. Self-teaching through IR makes this advanced phonics work possible.
Marzano and Simms are careful not to make grade-level generalizations. Essentially, they argue that independent reading is less effective for students in the "pre-" and "partial-alphabetic" stages of word recognition. Readers at those stages need a stronger foundation in phonological and phonemic awareness (sound recognition). Once they have this foundation, independent reading time is crucial. "[O]nce students can successfully sound out words, the best way for them to improve their reading is through independent reading."
By no means. The book discusses effective instruction in comprehension, fluency, and vocabulary, as well as phonics.
A text is a skeleton or blueprint for meaning. Real meaning is constructed in the head through inferring, synthesizing, using background knowledge, etc. If you think about it, how often does your understanding of a text include memory of specific sentences or whole paragraphs? Probably not often. Therefore, teaching students a small repertoire of strategies per unit can have a positive effect on comprehension. Mini-lessons and read alouds are the settings in which you deliver these strategies.
Yes. In fact, the book argues that comprehension instruction should begin even before "full-alphabetic" reading. Even the earliest readers need instruction in listening comprehension.
The book supports daily small group instruction, particularly for readers whose peers are reading independently. "It is imperative for students to enter the full and consolidated alphabetic phases as soon as possible so that they reap the benefits of independent reading for as long as possible." Students not at these stages need "phonics-focused, teacher-directed" small group instruction. Other forms of small group are also discussed in the book. Small group work continues daily even as a student begin conventional reading.
Marzano and Simms have a lot to say about assessment and, by extension, how assessment results are communicated. In general, they favor a "measurement perspective." With this approach, a teacher uses proficiency scales (a continuum of skills or a learning progression) to track a student's abilities in particular areas. Proficiency scales help the teacher match the reading behaviors they're observing to a level and then communicate this information to the student and parents, including next steps.
There's no explicit discussion of the workshop approach to reading in the book. The elements of workshop, however, are discussed at length: independent reading, structured conversation, small group instruction, succinct and direct whole group teaching. Marzano and Simms make a strong case for all of these pieces.
To the extent that anyone can, it feels like the authors strive to rise above the so-called "reading wars." In their introductory discussion of this debate, they cite research supporting arguments across the spectrum. In general, any participant in the reading wars claiming Marzano's work as absolute proof of their position should probably be viewed with skepticism. In general, The Science of Teaching Reading calls for a thoughtful marriage of word recognition and language comprehension instruction. "Here, it suffices to say that the current state of research in reading acknowledges the importance of both phonics and whole-language approaches."