In addition, I'm not happy with the section much lower down called Dialects, accents and varieties, but I’ll get round to that some other time.
We are told that “Most English dialects share the same 24 consonant phonemes”, and then (without any supporting evidence) that “Consonant pronunciation varies less between dialects than that of vowels”. I can’t think of any scientific way of measuring whether there is more inter-dialectal variation in one class of sounds than another, so the statement is meaningless. This paragraph says that some accents have an extra phoneme in “voiceless w” (as in ‘whine’), but it makes no mention of cases where accents have fewer phonemes in their inventory, e.g. where /h/, /ŋ/, /θ/ or /ð/ are not in the inventory.
The statement that “Within the same syllable, a vowel before a lenis stop is longer than a vowel before a fortis stop” brings up an old issue: the statement as it stands is correct, but the implication is that lenis consonants lengthen a preceding vowel within the syllable. This is a very widespread misunderstanding. As far as I know, the correct version is that fortis consonants shorten the preceding vowel, a process nowadays graced by the term pre-fortis clipping. Vowels which are not followed by any consonant tend to have roughly the same length as vowels followed by a lenis consonant. WP actually has a tiny article on clipping here. If anyone out there cares about pre-fortis clipping (come on, you know you do!) it would be a good idea to expand this article with some facts and references – there has been discussion about deleting it. In spite of that, the WP article on vowel length sets out a very clear statement that lenis consonants make vowels longer (using what seem to me to be completely unnecessary generative rules), so I think some harmonization is needed.
There is a table of vowel symbols for RP and GA, and for once we have a WP article that doesn’t bother with the oddball symbols used by Oxford University Press. We are told that “Vowel length varies between dialects and between words. RP has long vowels, … but in GA they are typically shortened”, which seems to me to imply that GA has underlying long vowels like RP but something happens to them to make them shorter. When we get on to regional variation, we find a confusing couple of paragraphs that talk about how we pronounce a combination of a vowel and a letter <r>, an example of the muddle to be found elsewhere when writers mix up spelling and phonemic representation.
Stress, rhythm and intonation
This section, which duplicates a lot of material in other articles, contains some badly written stuff. We are told that “English is a strongly stressed language”, a statement that needs some explanation. Later we read that “Stress in English is phonemic” – I’m not sure if anyone in phonetics nowadays would agree, but it’s certainly not how I use the word phonemic. Then we get “As concerns intonation, the pitch of the voice is used syntactically in English; for example, to convey whether the speaker is certain or uncertain about the polarity” – is this an appropriate use of the word ‘syntactically’? I doubt it. Then we get the uncritical generalization that “Rhythmically, English is stress-timed”, despite a more critical treatment of the stress-timed/syllable-timed distinction to be found in other articles.
Plenty more to work on in this very large article.