Cutting and pasting is a huge problem with large documents. The authoring tool split a paragraph in two. Yes Cutting and pasting is a huge problem with large documents.
Large documents translate rapidly using cut and paste.
Opening a file written in another application would not provide the detailed XML tagging. If you delete a section, the content within the tags will also be deleted. To restore a mistakenly deleted section, imediately press Ctrl-Z or select Undo from the Edit menu. Refer to the Authoring Manual for TSA for detailed instructions. This will insert tags for the heading and first paragraph of your subsection and allow you to insert the addtional paragraphs you want associated with this subsection.