Thedata on grapheme-phoneme correspondences in the dictionary and in text is readily avalilable [see Dewey (1971) and Hanna (1966)]. It shows that the vowels in most English syllables are spelled in one of four ways most (80%) of the time. In multi-syllabic words, the spelling patterns tend to be abbreviated or truncated which results in the five vowels (alone) being the most frequent way to spell 14 vowel phonemes. A pattern such as [oo] is the most frequent way to spell both /u/ and /u:/. In TO, there are many code overlaps.

Dr. Valerie Yule wrote, "The same spelling patterns can be the most frequent in representing different sounds, and they do not make a logical system either, so the 'most frequent spellings' are not the best guide for spelling reform." 

Although TO is not entirely logical with respect to the consonants, there is little disagreement as to what a logical system of consonant representation would be. Some prefer [c] to [k]. Some want morphological regularity with respect to plurals, etc. other want to system to be strickly phonemic e.g., [z] for [s] in dogz. In TO, [z] is the most frequent way to spell the /s/ sound.  See OGD. 

The checked vowels also do not present a major problem except for the vowel in "hook" /u/ which has the same spellings as the vowel in "hoop" /u:/.  The central vowel which is also represented as a [u] in TO is another minor difficulty. CKS represents the stressed mid vowel as u' and the unstressed central lax vowel as a' which seems to work fairly well for those who are not disturbed by the schwapostrophes. [a'bu't, a'nu'thr, a'baut]. 

The most common consonant spellings are usually obvious - no problems here, so not listed. 

a at, ax - fat cat - exceptions 
Guarantees to have salmon and meringue to harangue with plaits 
Ga.ra'ntiz tu ha.v sa.mn and ma'ra.ng tu hara.ng with pla.tz.  (CCS) 
gar@ntEz tC hav sam@n and mRaG (m@raNg) tC haraG with platz. (Unigraf) 

e elbow,edge - red hen - heavy heads 
I said I guess it’s nonsense that many friends pay with cheques on Wednesdays to bury leopards. 
'Y sed 'y gex itz nonsens xat meni frendz pei with cheks on wenzdi tu beri leprdz. 

i in, index, it - pink pigs - give and live 
Pity the city (final posistion) 
Pretty busy women build with rhythm on bicycles. 
Priti bizi wimn bild with rithm on bysiklz. 

o Hot dog 
What was 
Gone scone 
John got lots of honours and laurels because of his knowledge 
of how to cough on yachts. 

Jo.n go.t lo.tz 'v ho.nrz a.nd lorlz bicoz 'v hiz nolij 'v hau tu cof on yats 
Jan gat latz 

u  fun run 
Some come 
Son won one
Mothers and uncles with young blood have thoroughly tough tongues. 
muthurz and unculz with yung blud hav thuro'li tuf tungz. 

A  bake cake 
lazy baby 
l8zi b8bi pl8 d8 w8t for tr8n tu r8s m8z gr8t st8k. (possible grapheme)
lAzi bAbi plA dA wAt for trAn tu rAs mAz grAt stAk. 

play day (final position) 
wait for train 
raise maize 
great steak 

They reign at the ballet matinees with veils and bouquets. 
xei rein a.t x ba.lei ma.tineiz wi.th veilz a.nd bo'keiz 
xA rAn at xu balE matinAz with vAlz and bOkAz 

Eight straight dahlias in gaols. At strAt daalia's in gOlz. 

E real beat 
chief thief 
we be (final position) 
meet in street 
police piano 
please tease 
freeze cheese receive receipt 
The people believe in the key to the league. Eight straight dahlias in 
gaols. 

I hi-fi 
my try (final position) 
like to bite 
bright light 
flies die 
The guide on the island eyed the diamond in the aisle by the 
choir. 
But why sign to either with dye? 

O old gold 
no go (final position) 
boats float 
know the show 
The rogue of a chauffeur at the depot holds a mauve brooch on his 
shoulder. 
Folk know, though, that his beau was a ghost in Cologne. 

U refuse to use 
tuba music 
new stew 
emu menu 
rescue due 
You view Hugh’s beautiful ewe. There’s a deuce of a feud over 
the juice in lieu of an impugned fugue. 

ar dark car 
fast past 
pass glass 
banana in pajamas (final position) 
passed glassed 
Half the guard at the heart of the bazaar laughed at the sergeant’s aunt 
in bourgeois khaki. 

er her fern 
bird girl 
learn and earn 
word work 
cur’s fur 
The nurse’s answers to the amateur journalist were worse than the 
colonel’s circles of myrrh. 

air fair hair share care 
bear wear Where?There! 
The mayor’s parents spared their aeroplane fares. 

or sports sort 
poor door 
more stores 
ward off war 
George bore four swords on board his horse, of course. 

aw raw paw (Final position) 
ball wall walk and talk 
In autumn, Paul taught all his friends to fish and they brought back what they caught
In awtum, tawl Pawl tawt awl hiz frends tu fish and thae brawt bak whot thae cawt. (NS)
In autum, taul Paul taut all his frends tu fish and thay braut bak wot thay caut. (RES)
In otm, tol Pol tot ol hiz frendz tu fish and thei brot bak what thei kot.  (CKS)
in otM tol pol tot ol hiz frendz tu fiS and thA brot bak Wqt thA kot..  (Unigraf)

ow brown cow (final position) 
sound around 
mouse house 
Sauerkraut on the bough 

oy toy boy (final position) 
boil in oil 
The noise of a gargoyle on the life-buoy 

OO cool moon truly unruly | cuol, muon, truly, unruly
true blue to do                   |  tru blu tu du                  | 
a lulu of a zulu guru in a tutu | lulu zuolu  guru  tutu 
Choose fruit soup or lose two shoes en route to the manoeuvres. 
Chuos fruot suop or luos tu shus en ruot tu the manuvers. (RES)
oo look, a book    | look, book
put, push and pull  | poot, poosh, pool  (lots of visual disruption here)
could, would and should  |  cood, wood, shood
Wolf !   |  woolf

See George Lahey's analysis of traditional spelling and sound spelling.