This is not a bad proposal at all. (Except space after period, in markdown a single newline and a space is equivalent so having a single space then another newl

This is not a bad proposal at all. (Except space after period, in markdown a single newline and a space is equivalent so having a single space then another newline character is weird, not invalid though.) Many people do recommend this (newline per sentence.) This comes up for example in the issue tracker of pandoc. This is complete different as 2 spaces change the final representation, while newline-as-space in markdown source do not.