Count your blessings: it's way, way worse in French..

Respelling using only the 26 letters works pretty well for the General American dialect. The most unintuitive specific respellings (otherwise pretty easy) are:

  uu for 'oo' in "book". A relatively rare vowel but some very common words use it.
  dh for 'th' in "the". The two sounds of 'th' are not fully separated in English.
  igh for 'i' in "price". Common but lacks any unambiguous shorter spellings.

The second issue is trying to prevent the default rules from applying. [aeiou]_e is usually easy to fix by doubling the consonant, but that fails with multi-letter consonant sounds (splitting into syllables helps this one). The s->z change at end of words is very difficult to stop (we can easily respell "fleas"/"flees" to "fleez", but respelling "fleece" to "flees" is problematic). The only reason respelling usually works is because most words don't change into existing words.

The third issue, of course, is that there are many dialects with extra sounds (mostly original, but some later inventions), or different pronunciations for only a subset of words that are indistinguishable in other dialects. I have no idea what sound is used to distinguish "for" from "four" in dialects that distinguish them.

But the issue that almost never gets addressed is stress, which is not really a word-level phenomenon but significantly affects pronunciation. For example, "to" has maybe 5 different pronunciations just based on exactly how stressed it is compared to adjacent words (t, ta, to, too, tooo), and it also has variants based on what particular sounds are around it. I'd guess that stress variations exist for every semi-common word that isn't a noun or lexical verb (and some that are).

[dead]