Merry seems surer of her capabilities right now than she has been for years - and for that she has to thank Linford Christie.
Last October, having experienced four successive seasons in which hugely promising beginnings were followed by hugely disappointing endings, she moved to Cardiff and became installed as the only female member of Christie's training group.
After slogging through winter schedules set by the former Olympic 100m champion, and spending two months warm- weather training in Australia with Christie and the other members of her group - boyfriend Andrew Walcott, Jamie Baulch, Paul Gray and Darren Campbell - she feels stronger than ever before. The niggling back problems, and the knee injuries which have required two operations in the last couple of years, are - she hopes, she believes - things of the past.
By way of demonstration, Merry opened her season recently with her first 400m race, on a windswept Welsh track in Barry, which she won in 51.7sec. As shows of strength go, it was impressive, confirming both to Merry and her coach that her preparations had been well judged.
Merry, who was previously coached by Keith Antoine, admits she was taking aback by some of the training methods Christie employs. Specifically, she was surprised by how slowly she was expected to run for much of the time. But this, as she soon discovered, was an essential part of the Christie approach, something which had been handed down by his own long-time coach, Ron Roddan.
"It's no good running your heart out in December and January when it's the summer that matters," Merry said.
"Throughout the winter Linford got all of us running at an even pace, concentrating on tempo, with the odd speed session thrown in. It's not as intense as the work I did previously and it suits me to a tee considering my history of injuries."
So steady was the pace, indeed, that Merry was able to run comfortably alongside her male training partners. "It has benefited me a lot," she said. "I feel a lot stronger now. The last few seasons have been very frustrating because I have begun each one by setting a personal best and ended each one with injuries. When it happened again last year, that was the final straw. I just felt I needed to make a fresh start."
Merry talks like a veteran and, indeed, it seems as if she has been around for a long time. But that, as she points out, is because she became so well known so young. Her early achievements have proved a hard act to follow. Apart from anything else it took her nearly five years to better the time of 7.35sec she had set for the 60m.
"I was running so quickly then," she said. "I don't know how I did it. But when you are young, you can do everything..."
She does not accept, however, that her precocity has worked against her. "Everything happens for a reason," she said. "But now I feel as if I am starting again."
The 200m, in which she set a personal best of 22.77sec last season, will be the main focus of her attention. She plans to earn selection as Britain's representative in the European Cup at the end of next month. Thereafter comes the European Championships and the Commonwealth Games.
"It's exciting," she said. "Things are going so well at the moment that I can't wait for my races."
Merry and her training colleagues are being supported this season by someone whom she describes as being "from a different planet" - medical therapist John Sales. "I've seen so many medical people over the years that when we were recommended to see this person I thought `Oh yes? Well, let's have a look...' But he's been brilliant. He works to the Chinese pattern of points on the body which correspond to other parts. he doesn't use acupuncture, he applies pressure. For instance, there is a point on my ear which corresponds to my knees... It sounds odd, but he's got me through from October to now and I've only had to miss two training sessions."
Success is beckoning once again to an athlete who has suffered from having too much, too soon.