I think one of the reasons that Sissoko has been so good for us, is that we haven't been able to play the way we do best all season. A lot is due to injuries, but also the way we have changed the players to fit the system rather than the opposite. I have mentioned before that the introduction of Son as a regular starter has changed the way we play. I hate to say it and make no mistake, I love the lad, but it requires us to play differently than we did when we dominated teams, and we aren't very good at the back positions (getting Rose back helps a bit though). Both Son and Kane are instinctive shoot-first forwards, the difference being that Son is best when he creates his own changes, while Kane excels at the end of them. We have players capable of playing an extremely quick simple passing game, moving the play rapidly upfield with Kane as target, which coupled with our (at least formerly) high stamina obliterated 80% of the league. Now Kane has found himself as much the creator as the target, helping moving the ball forward, and we have no other capable target man than him. He cannot make those intelligent runs when he messes around in midfield or on the flanks. Our game has become cumbersome, laboured and more dependant on single player performances and a fair amount of luck again, since our best "hockey assist men" has found themselves playing drawn back midfielders. Both Eriksen and Alli are much better passers of the ball than movers of the ball, in fact we only had one great mover of the ball, and he plays in China today. Well, you could argue that Son is a great mover as well, but he is more Bale-esque than Dembele-sque (sque sque).
The mentioned quick-passing instinctive play we had made slower thinkers like Sissoko stand out like an elephant in a pig pen, and I don't think it's a coincidence that his revival came when we were forced to change up things. He plays simple and solid, tighten things up and is just what we need at present. But it infuriates me when I see "lesser" teams having a much more fluid attack, when I know we can do that twice as good. Our quick passing game was just as great as Liverpool's, the only difference being that they have much more pace in attack. It is also much more demanding chasing the ball than moving it, which can explain our tiredness since we lose possession much more often than we used to. I also think this is the main reason that Eriksen's play has suffered, he is one of the world's best quick passers with godly vision, but we have lost movement up front and no one is in the expected positions anymore. If he goes without adequate replacement (and who the hell would that be), I fear we won't even be able to get that beautiful play going again. He is the key to that. This is the way I see it, at least.