It seems that these functions are also orphaned:

TDecBinCABAC* getTDecBinCABAC()             { return this; }

const TDecBinCABAC* getTDecBinCABAC() const { return this; }
TDecBinCABAC::copyState( const TDecBinIf* pcTDecBinIf )
TDecSbac::load ( const TDecSbac* pSrc )
TDecSbac::load ( const TDecSbac* pSrc )

One more orphaned substance

const TComMv operator +

Well, the generic question is, whether a library should remove all functionality that is currently unused, or keep some helper functions that my be useful, if people want to experiment with the software. The + operator would definitely be in category of potentially useful stuff...

Yes, there are some more as "dump" or "Check3" that could be used. The proposal is to mark it in a somewhat explicit way why the code should remain in a reference, if there is a need to leave it untouched.

From the above lists, I think only

TComDataCU::deriveLeftRightTopIdxAdi()

looks like it should actually be removed as there is a direct reference to directional intra, which seems not to use this neighborhood anymore. The CABAC decoder load may also not be necessary, but as with the others I see no harm in keeping it.

The problem with marking library code as unused in comments is that nobody will care about removing the marking, when the code gets used again. Usually that happens in a completely different place without even noticing the comment.

Okay, generally I think the approach "keeping as it is by default for reference s\w" is justified in a more reasonable way than permanent fixing, though there are technical means to force people to trace the unused things.

r4389 and r4386 remove the functions that we agree on. Closing the ticket as fixed.