Steam-centric Issue: Steam Keeps RE-ADDING My "Deleted" Savegames

[Srpadget]

[Preface:  I am aware that the "correct" answer to this is to use Steam as an installation service only, then move my KSP install to some other location that Steam won't mess with and play from there.  Let's just assume that I have some doubtless-insane and totally-wrongheaded reason for NOT doing that, and try answering the question I'm actually asking rather than just telling me I'm doing it wrong...]

I am an advocate of the "save early, save often" school of thought. This habit usually serves me well. But not now.

I now have over 600 savegame files in my main ongoing career game. I CANNOT GET RID OF THEM. I mean, I can and I do -- big bulk-deletes of hundreds at a time, using the usual straightforward Windows shift-click and delete. The files vanish from my directory structure as expected.

But then when I restart KSP from Steam, Steam ADDS THEM BACK. I assume it thinks it's "fixing" my "corrupted/missing" files or some such, and if I were NOT doing it deliberately I'm sure I'd be quite grateful. But it's starting to take a long time even to display the "Load Save" dialog, and nigh-impossible to find the particular file I'm looking for in the game's UI.

How can I circumvent this, and force Steam to let me delete old save files I no longer need?

(Yes, KSP will let me delete a file from the "Load Save" dialog, but ... I can only select/delete ONE at a time. And see above re OVER SIX HUNDRED saves to delete. Surely there's a better way?)

[Gargamel]

You're doing it wrong.  

I recall seeing a very very similar thread on this very topic not so long ago.    Try digging through a search (good luck) to see if you can find an answer.  I think there was some automated resolution. 

[Srpadget]

Ah-ha!  As SO OFTEN happens when I admit publicly that I can't solve a seemingly-simple problem, IMMEDIATELY after posting the question I sorted out an answer that worked at least for me.  Posting here in case someone else has a similar issue and wants a similar solution.

My desired parameters:  delete the files I want deleted, while retaining the ability to use Steam's sync to cloud feature in the future--see above re being glad of this feature if my files actually WERE corrupted.  (So turning off cloud sync in Steam won't work for me, since it retains all those old saves and will 'restore' them the moment I turn the feature on again.)

The solution that worked for me:

• Start KSP
• Go to Settings and run in window rather than full screen
• WITH KSP STILL RUNNING:
• Go to Windows, bring up my save folder overstuffed with old saves
• Mass-delete old saves as desired
• (Optional) Go back to Settings and revert back to full-screen mode
• Quit out of KSP

Steam will re-sync its cloud files when KSP starts and again when it quits--but if done as above, it ends up syncing that folder to its state AFTER DELETING all those old saves.

I'll have to go in and do this again every now and then, but it lets me keep the useful parts of Steam's cloud-sync while still letting me declutter my saves.