This is I think the crux of the argument. I'll actually illustrate using an example FROM the actual game (these restaurant/carpentry analogies are beyond me

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Take for example what Remalithis used in the other thread. Flame Strike versus Fireball.
From what I gathered from Remathilis (correct me if I'm wrong) To many people, they're the exact same spell with what people consider a neglibile difference.
However, to me, there's huge tactical differences between the two. Even if you factor out the differences in range and area of effect, the spells perfectly encapsulate how 4e plays differently at the table.
With Flame Strike, you actually want to invest in resources that play with the saving throw mechanic so the rider lasts longer. Similarly, Flame Strike being able to hit ONLY enemies versus Fireball that hits ALL creatures playsa huge tactical decision point in battle.
In actual play, there's LOTS of times when Fireball is better than Flame Strike and the reverse is also true, and that's a prime example of how the actual choices matter at the tactical level.