The 30-year-old transferred south from Auckland eight years ago and his timing was perfect.
The Volts snapped a 20-year title drought with victory in the one-day tournament in 2007-08.
Otago is one win away from reaching this season's final.
It will play Canterbury in the preliminary final at Hagley Oval tomorrow.
The winner will play Central Districts in the final in New Plymouth on Saturday.
De Boorder is one of a handful of survivors from the successful 2007-08 campaign.
"I think there are a lot of similarities to when we did win it in '07-'08,'' de Boorder said.
The Volts had not played that well during the round-robin phase in 2007-08 but "snuck into the semifinal'' thanks to a confidence-boosting win against Northern Districts in Invercargill.
The Volts then went on to beat Canterbury in the semifinal and Auckland in the final.
Fast forward eight years and Otago was in similar spot.
The opening half of the campaign was disappointing but a heartening win against Northern Districts followed by back-to-back wins in Invercargill has put Otago into the preliminary final.
"It has the same feel. We are starting to hit our straps nicely at the moment. The boys are getting into some good form and I think we will definitely be dangerous. Other teams will start to look at us as a bit more of the threat now.''
De Boorder has not had to do much with the bat in recent matches with the top order of Michael Bracewell, Neil Broom and Hamish Rutherford all in great form.
Broom has scored three centuries during the campaign and is hitting the ball and pacing his innings as well as at any time in his career.
The Volts also boast an impressive bowling line-up featuring Black Caps Neil Wagner, Mark Craig and Nathan McCullum, while Jacob Duffy is getting back to the form he enjoyed last summer.
The all-rounder stocks have also been boosted.
"With Neesh [Jimmy Neesham] back bowling and Nathan McCullum coming back in the team, the balance of the side is quite nice really,'' de Boorder said.
"We not only have extra cover with the ball but a bit more depth with the bat as well.''
While the Volts have not won the one-day title since 2007-08, they have tasted success in the twenty20 competition, winning it in 2008-09 and again in 2012-13.
They made the final again this year but lost to Auckland.
"If you look at that campaign, we had a great start but were a bit inconsistent leading into the final, whereas it is almost the mirror image of that for us in this one-day camp.
"We really struggled at the start and then finally we got some things going and are starting to play our best cricket at the right time.''
Otago made it through to the one-day preliminary final last season but was eliminated by Central Districts, which went on to win the title and has made the final again this season.
That game might help to motivate individuals, de Boorder said, but it is not something the team had dwelt on.
Canterbury has beaten Otago twice this season and both times it defended smallish totals.
"They have a really strong bowling line-up - probably a lot stronger than some of the others in the competition ... and that has set them apart and won them a lot of games.
"Hagley Oval is a big ground with biggish square boundaries, so we are anticipating that they will come at us with short deliveries. We'll definitely be prepared for that.''
Canterbury also has an experienced middle order "and that is something you can't really buy for finals cricket''.
"It is the guys who react best under pressure who usually win these games.''
● Otago has named an unchanged team for the preliminary final against Canterbury in Christchurch tomorrow.
Otago team
to play Canterbury
Otago: Anaru Kitchen, Michael Bracewell, Neil Broom, Hamish Rutherford, Jimmy Neesham, Nathan McCullum, Derek de Boorder, Sam Wells, Mark Craig, Neil Wagner, Jacob Duffy, Craig Smith.
