

It’s kind of the opposite - the IPA gives you an unambiguous written representation for each sound, while OP is making an unambiguous sound for each letter.
So for example, let’s say that you keep misspelling ⟨cache⟩ as ⟨cash⟩. Inside your head you memorise “⟨cache⟩ is spelled like [katʃe]”, then next time you need to write the word you’ll be less likely to write ⟨cash⟩ instead.
It’s only partial, for things that I could reasonably misspell while writing Portuguese:
I picked those specific readings because they’re easy enough to pronounce but they wouldn’t otherwise pop up in my dialect of Portuguese. A good chunk of them are actually archaisms, like ⟨c z⟩ used to actually sound like [ts dz] some 700 years ago or so.