According to Gopher, dirty edits can cause instabilities with other mods, but I'm not really sure how much of "at risk" you are with not cleaning them. This is the first time ever that I've cleaned these files..

I just cleaned update, dawnguard, hearthfires and dragonborn, though, so I guess I'm "good".

I think it's you're supposed to leave those.

You can clean them, as long you http://www.creationkit.com/TES5Edit_Cleaning_Guide_-_TES5Edit.

Dirty edits can make your game all wacko, especially when you install more mods with dirty edits.

Wrong. Skyrim.esm is the one to leave alone, the others are safe for cleaning so long as it's done properly.

I applied a filter for cleaning, removed "identical to master" edits then lastly I undeleted and disabled deleted entries (as Gopher explained http://www.youtube.com/watch?v=fw3g_N1jcZQ). Now BOSS reports them clean but I still have the "bash delev relev" thing after them but I won't bother with whatever that means). I have no need for Wrye Bash and a bashed patch since I don't run 100+ mods.

Yep, I forgot to mention that it is the Skyrim.esm that needs to be left alone, Update-Dawnguard-Hearthfire-Dragonborn esm are safe to clean.

As for you CrazyGuy, it sounds like you got it right. Pretty easy, huh?

As for the Bash tags, you can ignore those. They are just suggestions, not warnings. You are like me, I don't want anything to do with Wrye Bash

When I first opened tes5edit, I was like that meme dog in the laboratory: "I have no idea what I'm doing". I consulted Google and found this Gopher guy, subbed him and watched a few vids, namely the one where he cleaned the masters.

Yes, it was very straightforward actually.

I did use Wrye Bash and created bashed patches back when I played Oblivion, but back then I pretty much always had mods in the 100+ range (sometimes even close to 200) but IMO that game NEEDED modding. With Skyrim, I don't believe it needs as much modding at all. I'm not sure if I actually need all the graphics mods I use, lol.

I used it when I first started modding Oblivion, but nowadays I don't use many mods so I don't find a need for it in any TES/Fallout game.

FYI, a dirty edit can cause a problem thusly:

Mod A modifies record XYZ

Mod B includes record XYZ (unintentionally with no changes) and does not list Mod A as a master.

Mod A is now broken, because its change to record XYZ are now replaced by the vanilla record (from one of the masters, skyrim.esm, update.exe, etc.).

The biggest culprit would be a change to an exterior block or interior cell, which would cause CTDs and/or major rendering problems. The Construction Kit accidentally includes these types of dirty edits a lot.

ITMs are more subjective as they could change something you like that another mod undoes. UDRs cause crashing and should be fixed.

It's not how many mods you have in Skyrim that determines whether you need a bashed patch, it's what the mods you have do. The 'delev' and 'releve' notes have to do with leveled lists. The bashed patch merges the leveled lists so that you don't lose changes from some of the mods.

Oblivion's bashed patch did a whole lot more, which is why it became so important. Skyrim's bashed patch only touches leveled lists and a few game setting tweaks.

Cheers.

Ah, that clears it up, thanks. Yeah, I remember from Oblivion that my game could insta-crash at load if I didn't have a bashed patch.

^ exactly