I'm using latex+vim+git for this purpose currently. I put two spaces after a period to signal the end of a sentence in Latex. Which helps me break the document up by sentences with vim.
If you're using markup then encouraging the period-double-space could be a harmless way of easily breaking the document up by sentences
If you're using markup then encouraging the period-double-space could be a harmless way of easily breaking the document up by sentences