Dallaglio has featured on the bench four times already this season, including for the 55-0 drubbing of Treviso, but has never been omitted from the team for a headline European match.
Yet back rows James Haskell, Joe Worsley and Tom Rees started in England's last RBS 6 Nations clash with Wales while Daniel Leo and Johnny O'Connor add further options in a highly competitive area.
Dallaglio admits the size of Wasps' squad has been a factor behind his ineffectual form this season but the club captain will still roar Wasps on from the sidelines if he misses out on Saturday.
"The team selection will be an interesting one. The England back row are all Wasps, so it might depend on whether you put country before club," he said.
"I may well win or could lose out but whatever the selection is I'll be committed to getting on the pitch and making sure we win. Things change quickly in rugby.
"My form hasn't been dreadful but our team has changed every week and I've found that quite a difficult scenario to understand because it's not really happened like that over the last three or four years.
"It has been difficult to get any pattern or rhythm to the team this season because we've lost so many players to international call-ups and injury.
"When those guys are back you have a platform to play from. No excuses, my season has not necessarily gone that well."
Leinster will arrive in High Wycombe with the competition's deadliest back line, including Ireland internationals Shane Horgan, Gordon D'Arcy, Denis Hickie and Girvan Dempsey.
The loss of Brian O'Driscoll to a hamstring injury is an enormous setback but with Felipe Contepomi pulling the strings at fly-half, they still have the tools to end Wasps' European interest for another season.
The suspicion remains that Leinster do not possess the forwards to seize their first European crown with last year's 30-6 demolition by Munster highlighting their Achilles heel.
But Dallaglio denies their pack can be targeted.
"Leinster are top of the Magners League so there can't be too many weaknesses there. There are some great sides in the Magners League," he said.
"They virtually have Ireland's back line and it's genuinely sad that O'Driscoll isn't playing because you want to see the best players on the pitch.
"They have threats all over their team - D'Arcy and Shane Horgan have been playing unbelievably well over the last two or three years, certainly since the Lions tour.
"I don't buy into the view it's our forwards against their backs. They have some tremendous forwards, including Will Green, who was good enough to spend 12 years at Wasps.
"It will be a fascinating encounter between two teams who play in the right way. We know we're playing a quality side packed full of internationals.
"When you play an international side you have to raise your game. But our team is also packed full of internationals, a captain of England and a captain of France."