I wholly agree with the rest of your message, but this sentence... in my experience thit is not so.
I often wondered about what gets to be shown in recent contributions and what doesn't.
The rule we know is that when a moderator edits your translation, you don't lose your sub count, and the sub still shows. And it shows as it was originally, not the edited version. Which is fortunate, because other moderators looking at your work can establish if you're good enough etc.
If you edit your subtitle yourself, then both versions are shown in Recent Contributions. Although I assume it still counts as one sub.
Test 1: subber edits herself
I had a look at an edited sub in one of the series I moderate. Here are the two versions the subber herself made. The first one in the bottom and the revised on top.
So far so good. We established that if she edits herself, both versions will show. I have encountered this many times, so I knew it already.
What if I, the moderator, edit her sub? Will something change in her Recent Contributions page?
Test 2: moderator edits subber's sub
Here I edited her sub adding -nim after the person's name. See it in Subtitle Editor.
But in her Recent Contributions page it only shows the one she made, not my edit.
I'm very glad about that, because it means that we can go and take a peek at new people's subs to decide whether they are good or not.
Test 3: moderator edits herself
There is a series where I am CM and segmenter, so I made a new segment somewhere (hoping nobody is watching right now), and wrote
I saved, and looked at my recent contributions. It was there all right.
Then I went back to Segment Timer and edited, writing "test sub changed" and saved.
Back to Recent Contributions, refreshed the page. The new change wasn't there. Only the original sub
Back to S.E. Another edit and save
Back to Recent Contributions, refreshing page. The new change wasn't there. Just the first subtitle, "test sub" (I"m not including a picture, it is always the same, just the timing shows "7 minutes ago" I assumed it just needs some time to show up.
In Segment Timer, I finally deleted the extra segment, saved and closed.
After ten minutes or so, all my changes showed in Recent Contributions. Except the deletion of the segment.
So you see, the moderator's edits don't change the subber's work in the Contributions Page. You can still go and judge how good she is by looking at it!