In the case of a countback, Tapp had to win at least two sets, which she did to lead 2-1 before dropping the fourth set and then staring down the barrel as she trailed 8-3 in the decider.
However, Tapp dug deep to take the next eight points in a row, winning the fifth set 11-8 to take the match and remove the countback from the equation.
In the final against Auckland, Tapp was beaten 4-1 by Lisa Cowlard, but Central still won the meeting 3-1.
Palmerston North teenager Kaitlyn Watts recovered from dropping the first set to beat Auckland's Sue Kim and claim her fifth straight A Grade victory.
The 13-year-old, who finished 17th in the individual competitions, is the youngest player to qualify for A Grade
No 2 Central player Danielle Fourie then accounted for Abbie Palmer in three straight sets, while No 1 Rebecca Barnett got past Ellie Epke after four gruelling sets, the last two having to go past the 11-point threshold, to earn Central's first women's team title after 42 years of the national competition
Darlington, who heads Central's high-performance programme, was ecstatic with the win.
"It's a fantastic achievement for the team. [They] had trained hard leading up to this event, knowing they had five days of squash ahead of them and that some would play up to eight matches during that time.
"A testament to this was nine of our 10 players were all playing on day three in the individual finals.
"So to see all our players completely empty their tanks on day five made our group feel pretty proud at the end of proceedings".
It was also vindication for Darlington, who had approached the Central Squash board three years ago with a plan to create a programme to bring national success.
"To do this in such a short time is a great feeling and knowing that what we are doing as far as planning, training the players and getting them match play is working."
He praised head coach Kashif Shuja, who is Palmerston North-based like all the players other than Tapp.
"Kashif is a five-time New Zealand champion and so his expertise and knowledge is massive to the young group of players that we're trying to nurture. "To have him training the players daily has been the backbone to this win - you just can't get anybody with his calibre so we're very lucky as a district.
"Along with Grant Watts, the women's coach also does a superb job with the team behind the scenes and on game day, so hopefully we can bring more titles home in the future."
The Central men's team, led by Shuja, finished fifth in the teams event, ahead of their seventh seeding. They beat Waikato on a points countback, 155-151, after the sets tied at 8-all, to take the Plate final.