I have to confess that I do use the slang "coulda", "woulda" and "shoulda" in texting and in these forums rather than the contractions "would've", "could've", "should've" because of laziness and ease of keyboarding. I'm an old school, crappy hunt and peck typist (is that even a word anymore?), so any shortcuts I can take, I will.
In formal, professional writings though, I do't even use the contractions but rather "could have", "would have" and "should have".
I also admit that that "could OF", "would OF" and "should OF" drive me absolutely insane. What the blank does "could of" even mean?

Good OP...TP