But that isn't the only reason he will be instructing driver Blair Orange to stay in front from the ace draw on Saturday.
"Her work on Monday was great even though we all know Spanish Armada is better on raceday," Jones said.
"But I couldn't be happier with my filly.
"She has had a long season and the only time she has really felt 100 per cent on top of her game was in Auckland before Christmas and I honestly think she is back to that now," he said.
"Her recent work has been super and the fact she missed the Oaks last start because she was a bit crook probably helped her.
"So we know she is well enough for a hard run and the shorter distance helps us because Spanish Armada is such a good stayer.
"I think everybody knows Spanish Armada is the better filly but we have the draw to park her and that is our best chance of winning.
"It also means the others back in the field will probably be reluctant to move because they won't be able to get parked, whereas if we let Spanish Armada run to the front then there will be more moves.
"That would mean we give up our advantage to not only one horse but a couple. So it makes sense to stay in front."
Delightful Memphis got as long as $8.80 with TAB bookies this week, a very generous price and over double the quote she has been with other bookmakers betting on the Jewels.
The pair look set to dominate the front end of Saturday's race after their best performed rivals, Bonnie Joan and Jewels defending champion Partyon, drew the second line.
Trainer Mark Purdon was happier with Partyon's work on Monday after two moderate recent performances and she downed both Delightful Memphis and Spanish Armada at last year's Jewels, but that was when leading.
Saturday could be Delightful Memphis's last start in New Zealand as she is booked to fly to Australia next Tuesday for a three-race Queensland campaign before racing in Sydney next season.
"I'd love to win a Jewels with her before she goes," Jones said.
"I've only won the one, with Rocker Band last season, so they are hard to get."
Jewels Day
Where: Ashburton
When: Saturday, first race 11.47am.
What: Nine group one races totalling $1.2 million in stakes.