なら〜で・たら〜で: the difference
なら〜でN1
Meaning
If
Past papers
Example
上司：「塗るなら塗るでもっと丁寧に仕上げなさい。」
Boss: 'If you're going to paint it, finish it more carefully.'
たら〜でN1
Meaning
Even if, If
Past papers
Tested once in past papers
Example
「もし失敗したら失敗したで、また最初からやり直そうと思う。」
'Even if I fail, I will do it again from the beginning.'
How to tell them apart
「なら～で」: about a not-yet-real supposition and a firm attitude. If you mean to do A or dislike A, go all the way, no wavering: 「やるならやるで真剣にやれ」.
「たら～で」: about coping once something has happened. Even if it does become A, there is a way then: 「失敗したらしたで、次を考えよう」.