Just as an aside, I can almost guarantee that you, Barney, have far more wild yeasts in your kitchen than I do right now. I have no bananas or other fruit on my counter, and no potatoes hanging around either. I have not made bread two or more times a week for months as you have said you are doing. And, not only are there two people who spend time in your kitchen (presumably your wife visits there once in a while) while I am alone here, but, I expect you are a larger person than I am (in other words, you have more skin area which means you carry more wild yeasts on your person than I probably do). And while you are not using whole grain flours, there may be less but there is still some wild yeast presence in the flour itself. Where I am right now, I have only a small amount of flour and it is well wrapped and still sealed - and in fact, is nowhere near my kitchen. Were I to make bread following your exact methodology today, I am fairly certain I would have far fewer wild yeasts competing for dominance in my starter than you probably do. My wild yeasts though, however few there are, would most likely be also of very different strains than yours. If I were to use exactly the same recipe, ingredients, method, breadmaker, everything exactly as you do, my bread would taste (at least subtly) different than yours, even if I lived next door to you .. because of the wild yeasts.
At any rate, I think you might be amazed at how much 'wild yeast' there is all around you - and hence how much 'wild yeast' may have settled into your 4 day commercial yeast starter and begun to grow. I'd be very surprised if there were only a few errant wild yeast(ies) lurking in your vicinity ready to invade your experiment. Time and temperature are probably the only reasons your starter had not become very sourdough-y tasting - had you left it longer and continued to feed it and/or had you changed the temperature significantly during the fermentation period that most likely would have happened as the wild yeast strains gained strength.
In any event, you will always have some wild yeast in your breads - it just isn't dominant as quickly when you both use commercial yeast at first and then end the experiment early (and particularly if you use commercial yeast and a bread mixer which rapidly converts the bread mixture into a baked finished loaf). If you don't want a strong sourdough taste (and as I have said not all sourdoughs are even recognizable to the average palate as being sourdough even if they are) that is fine - but to deny that wild yeasts are there at all is not plausible (or smart if you want to 'understand' what is happening so you can replicate it reasonably consistently over time). It is all a delicate balance between the 'flavour' that wild yeasts can provide through their ability to 'sour' the dough a little or a lot, and the amount of leavening you want, the amount of yeast you use and the amount the atmosphere provides, along with time and temperature - just to mention a few variables.
Have you tested the pH of your starter? That might be one way to see what is happening over time vis a vis the wild yeast 'takeover' (or not). Sourdough pHs are generally much lower (aka more acidic) than those of commercial yeast preparations. You may want to read this article about the difference between wild and commercial yeasts. http://www.nyx.net/~dgreenw/howdowildandcommercialyeas.html
But, speaking of 'fermentation' period, why did you decide to use the starter when it began to smell like alcohol? Starter goes through many phases (as it 'ferments', producing alcohol and CO2) - and will have different smells along the way - and many people might have waited till later in the process to use their starter (later than the alcoholic smell phase) ... so what made you decide that was the optimum time to make bread from it?
I have been making bread for many years, in many places, in many ways - but I am a mere amateur - and i am definitely not a 'scientist' but an 'intuitive' cook. I have made many mistakes - still do - and I learn from them (usually) and from the advice of others. I simply have an enquiring mind - as I am sure you do too or you would not be conducting this 'experiment'. As blue_dolphin pointed out - the best thing about eGullet is that we share our culinary experiences and experiments here - so rather than just get mad at people here who have asked questions or tried to share their personal experiences or insight or knowledge (or all three), and suggesting you may withhold your insights or results if we don't cooperate as you seem to want us to - why don't you just try to have a bit more of an open mind and heart. You may indeed discover some new thing that has eluded scientists and bakers for eons - we are open to that possibility and if it happens and you let us know, I am sure we will applaud your success. But, getting to that discovery may actually be made a bit quicker and/or easier by taking in/acknowledging there could be much value in the combined wisdom/knowledge/experiences some here have offered you and not discarding it out of hand.
