Let us not feel so bad about our progress!
Reading Masha Bell's article gave me the idea of sharing it with my students.
This sharing is meant for them to understand why we keep making mistakes in spite of our efforts. And it justifies my assertion as regards never leaving our interlanguage stage.

English literacy progress is slower and harder
I am now going to point out some of the consequences which result from the heavier English literacy learning burdens.Learning the sounds for the 185 English graphemes inevitably takes longer than learning to sound out just 50, which is the average number of spellings used by other Europeans languages. The 2000 words in which some letters don’t have their more common sound (women, womb, wombat – won, wonder) prolong the time needed for learning to read English even more.It is therefore not surprising that a cross-European team led by Professor Philip Seymour from Dundee university which investigated literacy acquisition rates in 13 languages concluded in 2003 (British Journal of Psychology):“Children from a majority of European countries become accurate and fluent in foundation level reading before the end of the first school year. ....The rate of development in English is more than twice as slow.”Establishing exactly how much more time English-speaking children take for learning to read is difficult, because there are great differences between individual pupils, and teaching quality makes a difference too. But we are unlikely to be far off the mark by guessing that a spelling system which uses three times more graphemes than others, is going to make the learning of basic letter-to-sound correspondences considerably slower. The 69 graphemes with variable sounds (ear heard heart) retard progress still further.Perhaps the task which beginning readers of English have to tackle can be more easily understood by contemplating learning a foreign language. The prospect of learning to sound out 185 spellings would be much more daunting than doing so for a mere 50. Having to cope with many additional words in which those graphemes have unpredictable sounds, would make the task even more challenging.I wonder if the literacy difficulties in their own language deter many speakers of English from learning other languages. As a foreign language teacher, I found many of my pupils pleasantly surprised by the ease with which they could learn to read other languages. Even Russian, in which many English letters have different sounds (such as p = r, m = t, y = long oo) caused them no difficulties after a few months – because in Russian the sounds of those letters are completely reliable.The other predictable consequence of any difficult-to-master system is a higher failure rate. Not many people could learn to use computers with the old DOS operating system, but the invention of windows quickly put computing within the grasp of millions. There is every reason to speculate that improvements to English spelling would similarly put literacy acquisition within the reach of many of those who are currently debared from it by the difficulties of coping with the irregularities of English spelling.Among those who learn to play the piano, violin or tennis, or practise to become a good runner, footballer or artist, the proportions of successful, average and failed achievers is much the same as with English literacy. Skills that require a special aptitude are completely mastered by only few. With perseverance, many can learn to be quite good at them too, but a substantial numbers never get beyond the basics, no matter how hard they try. The difficulties posed by the inconsistency of English spelling have a similar effect and prevent millions from ever becoming competent readers or spellers.Sadly, inability to cope with learning to read and write has a far more devastating effect on people’s lives than lack of musical, artistic or sporting talent. Making literacy more easily, and thereby more widely accessible would therefore bring enormous benefits.