Wales international James has scored more tries than any other player in the tournament's history, claiming 28 touchdowns from 57 appearances.
The Llanelli Scarlets wing, though, would probably sacrifice that significant personal achievement on Saturday for a place in this season's Heineken Cup final against Wasps or Northampton.
In-form Scarlets are bidding to become the first Welsh winners of a competition that began 11 years ago when Cardiff reached the inaugural final before losing narrowly after extra-time against French giants Toulouse.
But Llanelli must overcome a significant semi-final hurdle, with twice European champions and this season's trophy-treble chasers Leicester standing in their way at Walkers Stadium.
The Scarlets have twice failed at the same stage, suffering agonising last-gasp defeats against Northampton in 2000 and Leicester two years later. Each time, their conquerors went on to lift the trophy.
James, whose Heineken try tally has been amassed for five different teams - Llanelli, Pontypridd, Bridgend, Harlequins and Celtic Warriors - was part of the Scarlets side edged out 31-28 by Northampton at Reading's Madejski Stadium.
He said: "I remember we gave away a silly penalty that allowed Paul Grayson to step up and slot the goal. I knew he was never going to miss it.
"With the Leicester semi-final two years later, that does mean we hope it is third time lucky for us, but we don't dwell on the past. It is all about the present.
"This is the crucial part of the competition where you get no second chances. It is winner takes all, but if you want to win the title you have to beat the best in getting there.
"We beat defending champions Munster in the quarter-finals, and now we have to go one step further against a side who have a great European pedigree, appearing in three finals and winning the Heineken Cup twice."
Llanelli have marched into the last-four with a magnificent 100% record, producing jaw-dropping performances, especially through away victories over Toulouse and Ulster.
Only 1997 European champions Brive won the tournament without dropping a game, although if Llanelli secure this season's silverware they will do it by recording nine successive victories, compared with Brive's seven.