It turns out to be possible to exter in the minibuffer a command: flex-insert Note:Comment, which will enter a flex inset under the name Note:Comment, which looks, feels and probably behaves like the real thing... only, it's a flex inset.
I don't think we want this. The attached blocks it. Will commit soon. - Martin
Index: Text3.cpp =================================================================== --- Text3.cpp (revision 20094) +++ Text3.cpp (working copy) @@ -1680,11 +1680,16 @@ case LFUN_NOTE_INSERT: code = Inset::NOTE_CODE; break; - case LFUN_FLEX_INSERT: + case LFUN_FLEX_INSERT: { code = Inset::FLEX_CODE; - if (cur.buffer().params().getTextClass().insetlayouts().empty()) + string s = cmd.getArg(0); + InsetLayout il = cur.buffer().params().getTextClass().insetlayout(from_utf8(s)); + if (il.lyxtype != "charstyle" && + il.lyxtype != "custom" && + il.lyxtype != "element") enable = false; break; + } case LFUN_BOX_INSERT: code = Inset::BOX_CODE; break;