I will confirm about "reciting bismillah before each one of them" from a scholar but one thing we should make sure. The order / sequence of those surahs should always be the same as mentioned in the Quran. For example, we can not recite surah-nas before surah falaq, or surah falaq before surah ikhlas...
Yes I was told the same thing that order of surah must be maintained in salat but as we know, the Quran was placed in order much later than the prophet (SAW) time.
Was it recited in salat in the same order, before it was compiled?