Parking the argument about the defence for a minute, I do have some questions currently about our attack. Simms for me has had a long run in the team, but hasn't looked that useful for a while. Our wingers, mainly EMC and Sakamoto, have been instrumental in us scoring goals. Switch the formation and surely you leave less players higher up the pitch to work with Simms, and remove the effective wingers we have in the process.
On top of this, MvE has looked a lot better recently, and is starting to rebuild that connection with Sakamoto again. I appreciate the left side of defence is a problem, but as we have just gone on a crazy winning run, to change this after one loss does seem to be a bit of a panic move. The goals we have conceded have been stupid, rather than down to be being tactically outdone. In fact, we could probably do a shittest goal of the season to concede video as there have been so many this year all following a similar theme. We get complacent, we switch off, someone does something stupid.
I understand the arguments as to why people think this may be a good idea, but I personally wouldn't want to change the formation just yet.