"He was better than last year fitness wise and happiness wise," he said.
"The facilities [at Riccarton] are fantastic. Both him and Celebrity Miss settled in beautifully. But the weight was always the worry."
Addictive Habit has won races over all types of distances and all types of tracks, including his win in last year's Coupland's Mile.
"He won his very first start as a 2-year-old and it was a heavy11. He ran something like 1.17 but he's run some pretty good times. He's won on good3 to heavy11 and from 1200m to 2100m."
Jockey Sam Spratt paid tribute to Addictive Habit's ability to adapt so well. "Not many horses can win over such a wide range - he's an awesome horse." Spratt shared some of Somervell's concerns as the field left the back straight, but she believes the horse knew better.
"Coming around the corner at the 800, I thought he was gone for all money," she admitted. "I was under the pump and when he straightened up and balanced up, he really let down. He almost knows what he's doing more than me - he was almost half-pie going around the corner going 'the post's up there, darling - we don't need to go now'."
Somervell expects he will restrict the relation to Rough Habit to weight-for-age and set weight features.
"He's just an unbelievable horse and it's just so great he's part of my team because he makes any trainer look good - he's just a real warrior." Addictive Habit has also put Spratt back in the spotlight. "As a jockey you need good horses," she said.
"I was lucky enough to have Mufhasa for a bit and it's so good to have another great horse like him."