I've never really felt the need to get involved with the online debates. You guys usually do a great job of sorting out the stats of players. However I just read the comment above by ferge and I have to say I disagree with most of the suggestions. The thing is if you change him down to the stats recommended then you get a very different player. However I don't think the change in football system has been accounted for and his gradual return form. With that said I'll try to explain my point of view on each suggestion.
Res - 84/85 - I agree that he doesn't find himself in the positions he used to, but this is part of he way Liverpool play now and not down to a reduced ability. Yesterday the game against Newcastle Lucas was fantastic at responding to the positioning and passing of the Newcastle midfield. Which allowed Liverpool to dominate the midfield, recent games have been similar too.
EP - 76/77 - A slight reduction here would be fair, although we should consider that this might be down having missed the better part of two seasons. Personally I would say 79, 76/77 is too low, imo he is not that sluggish. Although he did get caught a bit yesterday, however he was able to recover and burst into a safe space, out sprinting Cabaye I think. Who is also 80 for EP, so maybe no reduction at all, at the most its a small difference.
DS - 73/74 - This is definitely down to the way he's been told to play, Allen did the same most of the time when he played that role. Its about moving the ball about not dribbling. However doesn't mean he doesn't have the ability anymore. If you reduced this down he'd far slower than he really is when he has burst out of trouble. I refer back to the Newcastle game, 78 is accurate.
Top Speed - 76 - Again disagree, he managed to track back with several players yesterday, who he wouldn't be able to follow if 76 was the number. And he would certainly fail to pressing as effectively as he does in real life, as he wouldn't get to opponents quick enough to close down the shot or block out the pass. Imo he isn't any slower than before.
Stamina - 86/87 - Agreed he is not as fit as he was, although I do wonder if this is temporary. Personally I'd go for 87 at this time.
Def - 77 - Lucas's positioning is amazing for a defensive midfielder, and his covering is fantastic. Defensively he has been a rock in the last four games, even in the Chelsea were he kept Mata quite most of the time. Not an easy task. He deserves 80 based on his recent performances, and the fact that this is what makes him such a good defensive mid in reality, and why Liverpool missed his so much earlier in the season. He allows Liverpool to dominate the midfield, and is a strong component in nullifying the attack. Why else would Liverpool have the second best defensive record in the Premier League? A good defense is only as good as its midfield protection imo.
BC - 81/82 - I can't say I've paid a huge amount of attention to this. But now I think about it his ball control is graceful and his first touch is very good.
Anyway thats the way I see it.
Premier League data backing up Lucas' Defensive capability based on average tackles per game played, Lucas tops the list...
Lucas Leiva - 4.4
Steve Sidwell -3.25
Mohamed Diame - 3.10
Ramires - 3.09
Pablo Zabaleta - 2.91
Craig Gardner - 2.53
Robert Snodgrass - 2.46
Thats far better than Scott Parker and Zabaleta, who are both on 78 defence (although Zabaleta is a right back). In fact this information might warrant an increase in Def when you consider he's spent most the season coming back from injuries. Although I think 80 is fine for now, as I'm not going to suggest an increase purely on stats. Although when you consider Liverpool have average possession percentage of around 58% then those stats look like a lot of tackles.