Lets be fair here. Since Vlaar came back and since the turnaround in Feb how many goals did we actually concede from corners? I don't remember many. Also, since Vlaar came back and since other players came back like Gabby, and since Delph started to play better and since Sylla strengthened our midfield, and since we played 433, we were MUCH tighter defensively. Admittedly we never had a clean sheet and we still conceded goals but in contrast to Mcleish's reign we are not a defensive team but one focused on attack, a certain looseness is forgivable while Lambert gets the squad into the shape he wants.
To really push on we need to be capable of clean sheets, absolutely. But I think the defensive problems last season were more to do with the overall squad. During the very bleak period over christmas our midfield was porous with the non-presence of Bannan and Ireland and an off form Delph, and on top of that we were relying on players like Herd and Lichaj in defence.
I think these signings we have made from January, Bacuna, Sylla, Okore, Luna, will go a long way to making sure that the bleak awful period like last christmas does not repeat. These have bulked out our options in defence and midfield. Not to mention how much better and more confident the players became at the end of the season.
I agree with much you say, but I don't think you need to be "loose" on defense to be an attacking team. On the contrary, our defense still needs tightening up. Our goals against must come down for us to have a chance.
Will Okore and Luna in addition to more experience be enough to get it done? Too bad Okore hasn't been able to play much in pre-season to form an opinion about him. Maybe Lambert can get our defense to play better as a unit. Although he's had one season to get them to play his way already, with not so convincing results.