I'd like to preface my post with one thing: I don't want to get our team into the mentality that we NEED another player to be successful in the playoffs. However, an addition or two would surely be good.
Tough call on which out of the two...but if we could get either a player like Jamal Mayers or Marty Lapointe in addition:
I'd take Guerin.
But if we are only eventually going to be able to land one player:
I'd take Tkachuk.
I think our priority right now is a big phsyical player over a fast, scorer. The Flyers game this week is going to be the most viewed game tape by our opposition in the playoffs. They will pin what the Flyers did to us that night, as a major piece to a winnng recipe to beat the Wings.
If we look at our stable of talent, there is no reason we should be looking for more scoring. The fact is, we have a slew of players that haven't been producing as of late (Lang, Williams, Cleary ((I thought I'd never be able to say that)), and Schnieder, Kronwall (who IS expected to produce offense)). In addition, with Sammy being hurt we're missing some points there as well.
I think if you look at the season up till now, we've been doing well in the scoring department, not great by any means...but good enough to be beating most teams on most nights.