So I decided to clean the Unoffical Oblivion Patch 3.2 using TES4Edit 3.0.15 even though the wiki says not to. And to my suprise it cleaned 4 identical to master records.
Removing: RajhansHouseKey "Ra'Jhan's House Key" [KEYM:000177F3]
Removing: SkrivvaKey "S'Krivva's Key" [KEYM:0000A07C]
Removing: BogrumGroGalash "Bogrum gro-Galash" [NPC_:0000A082]
Removing: BlockDetectionDialogue [FACT:0000AA3C]
[Removing "Identical to Master" records done] Processed Records: 92544 Removed Records: 4 Elapsed Time: 00:00

So, is this good or bad or what? I have no idea.

You should probably ask Arthmoor in the patch's http://www.gamesas.com/index.php?/topic/1164539-relz-unofficial-oblivion-patch-320-unofficial-patch-supplementals/page__st__100.

Actually, cleaning UOP 3.2 is a non-issue, or should be. Why? You'll want to supplement it Arthmoor's latest UOPS, which contains, amongst other things, a replacement for that esp. In other words, UOP v3.2 esp should not be in your load-order, period. You still install UOP, yes. But UOPS overwrites it as needed.

Your load-order will end up something like this:

04 CyrodiilUpgradeResourcePack.esm
05 CURP_Controller.esm
06 Unofficial Oblivion Patch.esp [Version 3.3.5]
07 Oblivion Citadel Door Fix.esp
08 DLCShiveringIsles.esp

Notice that 'Unofficial Oblivion Patch.esp' is listed as Version 3.3.5 rather than v3.2. That's because the Arthmoor-supplied UOPS version overwrites the original UOP-supplied version.

As far as UOPS is concerned, so far as I know that esp should NOT need cleaning. Arthmoor is good about that.

-Decrepit-

While cleaning mods is generally a good Idea, you might want to look at the http://cs.elderscrolls.com/constwiki/index.php/TES4Edit_Cleaning_Guide for more information. It lists which mods need to be cleaned, ones that already have been cleaned, and ones you should not touch.

Unofficial Oblivion Patch.esp [Version 3.3.3] is under the list of already cleaned. That would be the supplemental patch, and like Decrepit said, Arthmoor is good about keeping things nice and clean.