So I recently read about 場合 for the use of "situation, or circumstance". What is the difference between ～場合、, 場合は, and 場合には? My friend couldn't explain it. He just said you need to feel for which is correct. If I had to guess, I'd say the は is optional and thus can be replaced by the comma, and the には is for added emphasis. Is that at all close?
I'd say the は is optional and thus can be replaced by the comma, and the には is for added emphasis.
I agree with your guess. There is no tricky difference here.
One pattern I noticed was that in written language,
〜場合、 is much less likely to be used when in the second half of a sentence:
X の場合、Y しよう。
今日は雨だし、 X の場合は Y しよう。
But this is more about legibility and visual flow. Keep this in mind when omitting the
は, so you don't create a choppy sentence or an ugly “visual run-on”:
今日は雨だし、X の場合どうする？ (Good)
今日は雨だし、X の場合、学校行かない (Flow is choppy)
今日は雨だし、X の場合学校行かない (Harder to read)
今日は雨だし、X の場合は学校行かない (Good)
(In spoken language, as you may know, there won't need to be a discernable pause at the comma. 「Xのばあいがっこういかない」 with no audible comma will be understood just fine.)