The No 13 debate, and need to fill that void, has been reignited by Matt O'Connor selecting Luke Fitzgerald at outside centre for Sunday's arduous yet necessary trip to Italy.
Maybe it's just a case of getting Dave Kearney back on the field after cruciate ligament damage, rewarding Darragh Fanning's durability and progressing Fitzgerald's return to full fitness but there was further evidence on Halloween night of his ability to finally become a centre.
It was just for the closing minutes of that 33-8 victory but Fitzgerald broke the line with a rapid against the grain step before putting Mick McGrath over for the fifth try.
This idea goes back to 2006 when Eddie O'Sullivan paired Fitzgerald and Brian O'Driscoll is an Ireland midfield. If not for a horrid run of injuries since November 2009, he might have been moulded into a 13 by now. Like O'Sullivan, Joe Schmidt previously used him at 12 for Leinster.
Brendan Macken wears number 23 here which really means Fitzgerald will cover wing and fullback as well. Maybe he will remain the Jack of all trades. So long as this rare talent stays fit who cares?
Other additions to the squad see Jordi Murphy at openside, following surgery, while Jamie Hagan comes onto the bench behind Michael Bent and Tadhg Furlong. Hagan's a tighthead but played a little at loosehead during his 18-month stint at London Irish.
With Richardt Strauss demoted from Ireland by Rory Best's return, Kane Douglas in the second row, Jack Conan continuing his progress at number eight and Kevin McLaughlin captaining the side, the pack has a tough enough look about them to dominate their hosts. Dominic Ryan also returns as backrow cover having trained with Ireland earlier this week.
This proved a successful excursion for Leinster 12 months ago, winning 21-20, but they should deliver a far more comprehensive victory this time. With seven defeats from seven in the Pro 12, Treviso seem like a squad on the precipice of ruin.
So, Leinster to bring their win-loss ratio up to five-three.
BENETTON TREVISO: J Hayward; A Pratichetti, E Bacchin, S Christie, L Nitoglia; J Carlisle, A Lucchese; M Zanusso, D Giazzon, R Harden; T Vallejos, C Van Zyl (capt); M Barbini, D Budd, M Luamanu. Replacements: A Kudin, J Novak, R Acosta, M Fuser, M Swanepoel, L Auva'a, R Trevisan, J Ambrosini.
LEINSTER: Z Kirchner; D Fanning, L Fitzgerald, N Reid, D Kearney; J Gopperth, L McGrath; M Bent, R Strauss, T Furlong; T Denton, K Douglas; K McLaughlin (capt), J Murphy, J Conan. Replacements: B Byrne, P Dooley, J Hagan, B Marshall, D Ryan, I Boss, C Marsh, B Macken.
Referee: Neil Paterson (SRU).