[Notjohn]

I keep getting these emails about Metadata and Big Data and all that stuff, which has caused me to consider how I might add the subtitle to the title of the book. I found a Mobileread discussion on this, dated 2013, which suggested that the way to do it was Title / Space / Colon / Space / Subtitle (without the backslashes, of course).

Does that still seem acceptable, appropriate, advisable? I'm sticking with Epub2, so as I understand the matter I can't have a separate subtitle field.

Thanks for any light!