I can't use the sign for disabled because it is frequently used as delete (I used to use it for disabled long ago and stopped for this reason).
I agree with @ccstone, it cannot jump out, it is meant to fade in to the background because it is disabled. The examples with the sign draw your attention specifically to the disabled macro, which may well make it more obviously disabled, but is not a benefit overall.
In any event, it is on the todo list to look at, but whether I will do anything further with it I can't say one way or the other at this point.
OTOH, it can't be so subtle that we don't notice it, or can't read it.
One could argue that since we can HIDE all disabled macros/groups, that when we show them we might want them to jump out, or at least be very obvious.
I have seen some posts where the user could not determine why his/her macro was not being triggered. Turned out that it was disabled. I know your "Assistance" helper will identify that, but I suspect most users are just first looking in the KM Editor to figure out why.
I can't really think of another app that is analogous to KM in terms of disabling items. Disabling menu items is not the same thing.
The best example I have is Outlook 2011, where I have set certain categories of Contacts to have certain colors, and that is reflected in the email I receive:
All of these remain very readable. Black is "normal", and any color has a special meaning to me. So I can quickly glance at the list and pickout what I need to.
I submit we need something like this with KM. I know you hate Preferences, but there are just too many different views in the world to force one view on everyone. So, if the user could set a color for "disabled" macros/groups, that might really help. If you and Chris prefer a light grey, then so be it. If I prefer a brown/orange, then so be it.
You're already using a light gray in the Global Macro Group that's in-between the shades being discussed here. Perhaps that shade of gray would at least be an improvement for inactive macros.
Hi. I have a suggestion — consider it scrawled on a napkin (I haven't pondered this, but it's pulled my eyes): add a grouping option to the Macros column in the Keyboard Maestro Editor window, with the only option being "Group by Enabled/Disabled status". In use, I would leave this on permanently — and in fact would find it easier to parse the information in the window were it presented this way. (For me, the enabled/disabled status is a more important, and thus higher-level, characteristic than the first letter of the macro name or the first character of the macro keyboard shortcut.) I recommend keeping the half-toning of the text color.
At the risk of weakening my argument, this kind of grouping within a display column can be seen in Path Finder. (The risk is that there are a lot of things in Path Finder that are not well-implemented.) I don't use this feature in Path Finder often — but when I do it is very helpful.
I suppose there could be an elegantly presented third control in the column header that sorts the list by enabled/disabled status. Since this is binary, the previous sort by either name or shortcut would be retained with the two groups. A simple check-box in the header might work. If enacted, I think it would be helpful to have a separator — a blank line will do — between the groups.