1) Why is the a marked long in the suffix a-ble even if it’s not said that way? Because the suffix base on its own has a long a (able)? or for spelling purposes only or both?
It is just for spelling purposes. In real life, the “a” is a schwa. Over-pronouncing the “a” distinguishes it from “ible.” All of this is really irritating in the early years, but come 7GRD, it’s super-great to be able to eliminate options for spelling mistakes. Kind of like, do you ever say /dok tOR/ in your head to spell it right? No one says it that way in real life, but we can hold an alternative pronunciation in our minds to help us spell. Accenting every syllable “for spelling” creates a verbal map for spelling a word, no matter how it’s said in regular speech.
2) I know valley is read-to-spell as /val -li/. Same for baby and /bay-bi/. Is it because that’s how they were said in the past? Or just for spelling purposes alone (short-I use y rule)?
It is just for spelling purposes. And while it feels DUMB in the easy words that kids learn to spell easily, it really comes in handy later when words get hard. It’s the easiest way to “mark” them with your voice and make sure you always get the “i” where it belongs; it sets those words apart in the mind from “ee” (employee) or “e-e” (concrete). Spalding has a whole page on it.
3) Syllable division – Some syllables are divided differently than the hand-under-chin rule – at least the way I understand it anyway. Maybe it’s my accent.
Hand-under-the-chin will give you the number of syllables, but not generally the “official” syllable division location on the books. Pronunciation differences tend to slide the consonants around. Spalding uses the official dictionary divisions, not the typical spoken ones. Like, I say /feh-ther/ for “feather” but Dictionary.com (when you click the syllable button) gives me feath-er. There would be no way to accommodate for how everyone says words verbally, so the dictionary division is the great unifier here.
4) How do you explain how most Americans say the following words (fire, choir, our, hour) with TWO syllables instead of one? Even the online Webster’s gives the option of a 2nd syllable, though an old print copy from the 90’s still only gave the one syllable option.
These are special sounds in rhotic speakers. Sliding from a stand alone vowel sound to an ‘r’ is a weird mouth move for us; it creates the illusion of a second syllable that isn’t there. Contrast “flyer” with “fire” below. Most speakers give “flyer” a stronger 2-syllable sound than “fire.” Even the pronunciation markings are slightly different; the “2nd” syllable in one is an “r” while the other has a full “er”. Brits and other non-rhotic speakers often barely say that ‘r’. It’s way easier on the mouth and keeps it one syllable, but it’s not great for remembering how to spell it. I would recommend sticking with Dictionary dot com (instead of Websters) since it shows the difference between official syllable division and the common pronunciation pattern.
5) People with my accent notoriously pronounce them fahr, kwahr and ahr (sorry can’t mark Spalding way!)
You are illustrating exactly why having a separate standardized pronunciation for spelling is so helpful. It frees up the regional pronunciation difference. Kids have no problem learning two pronunciations. Do you say “wed-nez-day” in your head to spell Wednesday? It’s the same thing. Making a spelling system that is representative of actual speech is really complicated. Additionally, it would have to change from region to region.