Frequent tipster Leonid Nemirovsky advises us on some of the differences between single-line and multi-line text in AutoCAD. He discusses dealing with justifications after mirroring either form of text.
"I think by definition Text and Dtext have very little capability for editing, or intelligence, if you will. They have simple processes, such as keeping their justification when mirrored. Mtext is more complicated; it has word processor–like capabilities and will change justification when mirrored. Here's a quick fix: Mirror Mtext (assuming mirrtext=0); double-click on mirrored mtext; inside the editor do not highlight it, just click on the appropriate justification in the toolbar. It will hold the Mtext object in the proper position and reset the justification."
Notes from Cadalyst Tip Patrol: Single-line and multi-line text will behave differently when mirrored. Assume, for example, that we have three rows of text, left-justified and aligned with the left edge of the text. If we mirror them so that they are all now aligned on the right side, we have to deal with their justification. Single-line text rows will align on the right, but retain their left justification. Multi-line text will also align on the right, but change the justification to be on the right. Single-line text only mirrors the content of the text, not the justification. Depending on what you need, use the text type that is appropriate for your project. If you want the Mtext objects to retain their justification, you will have to go back and change it.