It is our opinion that this approach to teaching reading & writing is
the major cause of the high levels of illiteracy across the English speaking world.

"Reading is a psycholinguistic guessing game." (Kenneth Goodman)

The denial of the value of teaching systematic/synthetic phonics.
That English is a language with a very powerful alphabet code is dismissed out of hand. The value of learning the code is diminished in favour of context dependent whole word guessing. Low visual memory locks students (as many as 30% on average), out of the opportunity to learn with any degree of accuracy.
The disregard of cognitive development in the early grades
particularly the introduction of predictive cuing to assist word recognition, which is

a) too cognitively demanding for most early learners.

b) an increasingly redundant strategy, with only one sentence in 8 yielding a result for the competent reader.

(However, predictive cueing is useful for vocabulary acquisition in already skilled readers)
The teaching of 'guessing'
with little understanding of the still developing visual memory of early learners.

(We treat 'guessing' as an error pattern and discourage it as a strategy. It is difficult for the learner to eradicate this once it is learned. It is also a habit that does not support spelling.)
Visual Memory Development
Children with low visual memory and low phonics fail to get off the ground in reading.

Children with high visual memory and low phonics will become dependent on 'guessing from context'

The difficulty arises when visual memory plateaus around 9 years of age. Words become longer and too visually similar for 'guessing' to be accurate. Often not enough words in a sentence can be accurately read for context to be of any help. Such children 'hit a brick wall' in learning . They enter high school with the reading age of a 10 year old and the spelling performance of a 9 year old. See VAS Ceiling and the video ‘Eve’s Story’
Whole Language
On Constructivism/Whole Language, the majority of good teachers would agree with much of what is being advocated - but certainly not to the exclusion of other necessary learning experiences OR the ignorance towards infant development.

The representation below is taken directly from Brian Cambourne's web page, so it's in his words. He is one of the leading whole language advocates. The US has Kenneth Goodman, the UK has Frank Smith & Australia has Brian Cambourne

We do NOT advocate this approach to teaching reading in infant grades. We maintain that infant learners are NOT mini adults and that their cognitive processing is qualitatively different to that of adults; as such their cognitive development must be respected.

From the text below:
“The teacher reads to the students and shows how it is done through demonstrating how to use a book and sounding out letters and words (phonological)” Note that this is arbitrary dipping into uncontrolled text. All of the golden rules of teaching are dismissed out of hand. There is no sequence, no structure, no practice and no consolidation. Imagine you are learning a new language, how much would you remember and use of this hit & miss approach let alone impulsive infants?

In addition to being read to from "big books," children in whole-language kindergarten classrooms write on a regular basis, even before they know the conventional spellings of words. Using this "invented spelling" a child in such a classroom might write a journal entry that reads: "Mi dg haz a yelo coler and a grn lees" (My dog has a yellow collar and a green leash). In addition, children in whole-language classrooms often collaborate on writing projects, creating their own "big books."

Even in first and second grade, teachers in whole-language classrooms overlook misspellings or misreadings. If a child reading out loud from a book says "chair" when the word in print is actually "seat," the teacher does not "correct"him or her. Rather, such misreadings are viewed as a natural step on the road to reading competency.

cambourne model
Chart above is by Brian Cambourne

Cambourne outlined a set of conditions which provide a foundation for learning literacy skills in the classroom. These are designed to simulate the conditions that occurred naturally when children learned to talk.
1. Immersion
2. Demonstration 3. Responsibility. 4. Expectation. 5. Approximation 6. Practice 7. Response. These conditions are the ground work for teachers from which the following reading activities can take place.
Modelled reading is essential to show children how to read. The teacher reads to the students and shows how it is done through demonstrating how to use a book and sounding out letters and words (phonological) , pointing out words, sentences and sentence structure (grammatical) and comparing text with pictures and getting meaning from what is being read (semantic reading). Modelled reading needs to be fun and informative, big books are a good resource for this activity.
Guided reading this is where the teacher, parent or assistant reads with the student in a one to one situation. The student demonstrates their reading abilities through exploration, problem solving, risk taking, self correction and comprehension.The assistant helps through support, guidance and prompting the atmosphere needs to be encouraging and positive.The students phonological, grammatical and semantic abilities can also be assessed in this situation.
Independent reading. The teacher sets up conditions for students to read and explore books on their own or in small groups. The student selects the book, find words and meanings, practices reading and might discuss and record what they have read. (The above methods have been gathered from the lecture notes: Teaching Reading a K-6 Frame work)

“Reading and writing don’t inevitably go together.  You can read without learning a thing about writing, grammar, or spelling, although, you certainly can’t learn anything about writing, grammar, or spelling unless you read.”  
(Frank Smith)

A link to the web site is given for those wishing more information on this approach.