The mechanic you describe requires you to dps through the 'holding in air' phase while hitting synergy to mitigate his damage. If you do sufficient damage to drop his shield he drops you and resumes normal attacks but will return to that mechanic if not dropped soon.
So, it's possible but requires timing and ensuring you have lots of dots on nerieneth and maybe some heavy-damage ultimate with duration just before he picks your character up to chew through his shield. Healing doesn't help - it's just dps, unfortuantely.
edit: White gold tower can only be soloed with a pet sorc due to harvester boss cage mechanic which resets the fight. Despite claims to the contrary other classes can't - I tried after someone posted on forum that was possible with other classes but that cage mechanic resets the fight. I couldn't use gap closer to escape cage in time, couldn't force lock etc without the boss resetting once inside the cage. I would, however, love to be proved wrong about this.
The mechanic you describe requires you to dps through the 'holding in air' phase while hitting synergy to mitigate his damage. If you do sufficient damage to drop his shield he drops you and resumes normal attacks but will return to that mechanic if not dropped soon.
So, it's possible but requires timing and ensuring you have lots of dots on nerieneth and maybe some heavy-damage ultimate with duration just before he picks your character up to chew through his shield. Healing doesn't help - it's just dps, unfortuantely.
edit: White gold tower can only be soloed with a pet sorc due to harvester boss cage mechanic which resets the fight. Despite claims to the contrary other classes can't - I tried after someone posted on forum that was possible with other classes but that cage mechanic resets the fight. I couldn't use gap closer to escape cage in time, couldn't force lock etc without the boss resetting once inside the cage. I would, however, love to be proved wrong about this.