Gefilte
“not everyone agrees that the Avos kept the Torah before it was actually given, as there are many complications with that”
Well chaza”l or of the opinion that they did keep the mitzvos (though there is a machlokes exactly which, when). So i dont know what you’re talking about.
“After all, understanding the reasons for mitzvos often helps us determine who/when/what circumstances the mitzvah applies”
False.
We pasken לא דרשינן טעמא דקרא so it would not help understand who when what.
But still its limud hatorah to (try) to understand the mitzvos. Just its not on a practicle sence. If you’re interested in knowing the mitzvos in the practicle implaction just open a gemara and learn day and night. And so with a שו”ע doing That is sure to help understand the mitzvos. But not writing
in a coffe room!
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