🚀 go-pugleaf

That makes more sense, though I still see far too many problems with it to make it a workable solution. One of the major problems I see is that it's an option only if the text is to be set ragged - because FM has no force justification, you can't simulate a justified "style guide" paragraph with individual one-line "FM" paragraphs (to use your terminology). As you've said, it also makes editing text a hassle, and if you want to export your text at any later stage you have to similarly go through and remove them your hard returns.

You also said that "My suggestion ... would work if the original poster has a body text format of say 12pt on 14 with a 6 point inter para space". This would mean that the effective line spacing of lines in your nominal style guide paragraph would be 20 points, which is certainly on the large size for 12-point type. So, your method would still likely require editing of the styles, which I thought was the reason you rejected Riley's suggestion to start with. In addition, if you want to use interparagraph spacing (between style guide paras), you also end up having to create more styles to achieve that.

I also find it hard to follow your argument that hard returns offer an advantage over soft returns because "the upper and lower spacing around a paragraph ... [is] applied to all lines ... [thus giving] a consistent and regular spacing". This implies that even spacing is not easy (or even possible) to achieve using soft returns, when nothing could be further from the truth - it's a very simple matter to achieve even spacing with soft returns by adjusting the interparagraph spacing settings.

Dominic