I think too many Liverpool fans think back to the Mascherano/Lucas partnership when making opinions about this subject. Lucas was a decent player back then, but he's improved so much now and is ten times the player. I actually think he'll flourish in a proper central midfield role as he's so intelligent that he'll be able to adapt and tweak his game where necessary. If you have another attacking midfielder ahead of them, ala Gerrard or Henderson, it'll give us an extremely strong base from which to start from. I think our problem at the moment is that we're physically weak in central midfield and at the moment the opposition are bullying us. Unfortunately, we don't have the philosophy that Barcelona have so we cannot overcome this by just passing our way through it. We need players that can stand up, dominate and take control.
Too many fans still think Mash/Lucas was shit or uncreative because they compare it to Mash/Alonso and also wilfully ignore just how shit Gerrard was in 09/10 - they talk up Alonso's brilliance but totally ignore any role Gerrard had in that or the subsequent 3, it's like it was all Alonso all along and Gerrard hit a random good season that just happened to benefit from it.
Fact was that Mash/Lucas was a fantastic CM that pisses over pretty much anything else this league has to offer, and indeed was incredibly strong then even though Mash was an appalling partner for Lucas (in that he pretty much didn't pass to him, ever), a partnership that still dominated most of the opposition we played, that still (whatever the revisionists and the deluded may say) made more than enough chances to win most games we played, and in front of which both Gerrard and Torres were having problem seasons - the one somewhat unfit and just absolutely wank, really poor form, the other still putting them away but often injured, sulky when not injured, and with both playing selfishly and neither showing any real leadership or team effort.
I'd swap Gerrard, Adam, Henderson AND Spearing for Mash, right now, and think we'd gotten nice deal out of it.