For me he is as important as VVD to the team. What an outstanding buy.
I think he's more important because of who he replaced. We'd had weak goalkeepers for close to a decade if you include Reina's drastic downturn in form from c. 2011, whereas our central defenders have rarely been weak during that time-frame; they've just not been top bracket like VVD.
A goalkeeper with poor technique and/or poor mentality would have eventually crumbled in that second half. Let's be honest Spurs peppered our goal with some decent strikes. For him to avert all of them from the danger zone was phenomenal.
He doesn't get the recognition because he's very orthodox in most ways. Whereas a goalkeeper like De Gea reacts much later, as well as utilising his legs more often, which can make his saves look more spectacular. But actually his save rate is consistently worse, especially from distance.