So, given that rogues unlock special methods like gruesome technique, signature weapon, skirmish maneuver from level 7 onwards, I thought it would be cool and thematic if they could unlock their improved versions in epic levels for those few builds that actually don't go epic dodge alongside all its prerequisites.
Just more options generally feels good, and I don't think these would be gamebreaking. Full disclosure, leveling a STR rogue right now, so I would definitely consider picking these feats if they became available.