(Correct outlines 2,3,6 conform to Anniversary and Simplifed. )
I find that with my pronunciation, as a dweller in England (especially in the south east), that when Gregg says to omit minor sounding vowels when appropriate I find myself omitting, at first, many ‘e’ vowels towards the end of a word.
For example when I wrote ‘recurrent‘ I wrote  rather than . I would pronounce the ending as ‘rnt’ (blending the ‘r’ into ‘n’ with a very short kind-of-a grunt, if anything, between them), but I assume that Americans pronounce it ‘rent’ with an emphatic short ‘e’ sound. [Perhaps this is why (in addition to the longer history of writing Pitman and the widespread establishment of Pitman colleges) the Gregg system did not take hold quite so strongly here as in the USA.]
Another, but contrary, example is ‘futile‘ which is written as  rather than . The ‘i’ for me is a major vowel; far stronger than the ‘e-u’. Because I know I need to bias my thoughts towards the American pronunciation I might even have written  — the ‘u’ sound so often in USA being shortened to a single vowel rather than a diphthong, for example in the word ‘duel’ .
Are there any English people, or anyone, out there who have found the same, and have to make special cases of some of their words? I know it is not too much of a problem really (certainly far less of a one than coping with the weird spelling of so many English words!), but it does bring me up a bit when I find them. Are there any rules of thumb which might help me out?