Ruaridh McConnochie has dismissed criticism of the rule allowing players to switch countries and says he is desperate to fulfil his "childhood dream" of playing for Scotland.
The London-born Bath wing, 31, featured for England at the 2019 World Cup.
However he can represent the country of his parents' birth because three years have passed since his last England cap.
"People disagree about the ruling but I think 'why not?'" he said after being named in Scotland's Six Nations squad.
"Your career is short - why shouldn't you go for the most you can?" added McConnochie, whose mother grew up "a stone's throw from Murrayfield" and whose Glaswegian father moved to London in the 1980s.
"It's been pretty surreal. I couldn't quite believe it when Gregor called me. It was pretty cool.
"We were born in London, me and my brothers, but my dad is a very proud Scot. He has supported Scotland all his life and played or had a trial with Scottish Schoolboys.
"We grew up with all the stories about his favourite players. It was always in our thoughts that we were Scotland fans.
"But not being in any academy I had gone to university and ended up playing for English Universities. I had messaged the 'Exiles' programme for Scotland and never heard much back."
If head coach Gregor Townsend gives McConnochie - who scored a try against the United States in one of his two matches at the 2019 World Cup - game time in the Six Nations he would become the first player to represent England and Scotland in the modern era.
The Scotland coach, who selected former Australia back row Jack Dempsey during the autumn Tests, met McConnachie in Bath last October and told him he had been on his radar since the eligibility rule changed.
With Edinburgh's Darcy Graham injured, McConnachie is competing against the recalled Sean Maitland of Saracens and Glasgow's Kyle Steyn for a place on the opposite wing to Duhan van der Merwe of Edinburgh and the British and Irish Lions.
Townsend's side start their Six Nations campaign against England at Twickenham on 4 February before hosting Wales seven days later.
"It's a foot in the door," said McConnachie, who prides himself on his work rate and his love of "getting on to cross kicks and high balls".
"Being in the training squad is a step in the right direction. I'm not getting any younger and I want to make the most of it.
"Darcy and Duhan have been, in my opinion, the most impactful wingers in the world in the last few years. It's a good platform to chase.
"They're such different players, physically, but they offer so much in different ways. It's good to look at how they make Scotland better."
McConnochie's Bath team-mates Josh Bayliss and Cameron Redpath will be welcome company in the squad for a player who describes himself as "a quiet, awkward bloke".
He says his dad, who lives near Crieff, was "pretty ecstatic" when he told him about his call-up, and that it was "probably a bitter pill for him to swallow when England Sevens came knocking" but who supported his decision nonetheless.
McConnochie, who has "an immense amount of pride" at winning two England caps, added: "At the time we thought that was me saying goodbye to Scotland and my childhood dream.
"I'm so happy that it's come round and to get the opportunity to train with the squad and try to push into that 23 is really cool."