dublinpilot,
To me, a "precautionary diversion landing" is something you may do if the weather at your diversion isn't good enough. That seems obvious. Your planned destination is socked in with fog or similar, perhaps. What are you going to do? You can't go there. You could return to base, but maybe the weather will improve later, maybe you don't have enough fuel, maybe you're becoming dangerously fatigued! So you divert to the nearest airfield with suitable conditions, and land, as a precaution. If that isn't a "precautionary diversion landing", I'd like to know what it is.
I'm not commenting on whether pilots do or don't abuse the scheme; it's irrelevant to the thread.
UV, my apologies for continuing this. I think you're right, but maybe there are some words and definitions here that need clarifying. If so, further disuccion might possibly be useful. But feel free to delete the thread if you want. And spekesoftly, I get the impression that UV wants to delete the thread due to the numerous digressions and misunderstandings of his/her original point, not because of differing opinions. Which seems hardly surprising to me!