Burnley's first goal was a set piece mistake. Nothing to do with numbers
Burnley's second goal, DCL, Gordon and Kenny all got skinned within about 2 seconds and let their full back get to the by line. How many numbers do we need to try putting in a challenge.
Burnley's third goal game from switching off from a throw, and a horrific clearance by Godfrey.
None of those goals are anything to do with numbers. They are entirely caused by a lack of responsibility and inexplicable errors.
I think it should be less about 'getting men behind the ball' and more about actually coaching the defence effectively and trying to limit the extent to which our mentally and physically
slow defence is exposed. You can do this two ways; either you control the game by winning the ball back and keeping the ball effectively, thereby reducing the time the opposition have on the ball ergo less attacks. Alternatively, you can reduce the complexity of what the defenders have to do by playing a lower line - Keep It Simple, Stupid - get the defence off the ball ASAP, don't let them venture too far up the pitch so they can stay in position and essentially get them to do something that they can be coached to do. It's not about 'numbers behind the ball per se', but more about
congestion - train the team to block shots, win their battles, and make it difficult for the other team to play through you.
We currently do neither - on the former, Burnley had more of the ball than us yesterday (which I believe might genuinely be the first time that's happened for them all season) because the squad has no confidence and is mostly turgid in possession. On the latter, I think it's fairly self-evident from the goals (and what limited videos we have from the club account, which are mostly possession drills) that there isn't much defending going on in training. People will point to the third goal as an individual mistake, and fair enough - it's a relatively innocuous ball in that a miskick turns into an opportunity. But the response to the miskick sums up that these players either aren't being coached or they don't have the discipline to stay in position - see how they charge Weghorst and leave Cornet completely unmarked on the literal penalty spot.
The worst example is actually the second goal - they have plenty of time to steady themselves and find their man ahead of the cross coming in, because Kenny gets rinsed miles away from the goal. Go and watch the second goal again, and each time watch a different defender - you'll get a sense for what I mean about their not being much defensive work on the training ground. In this sense, the errors aren't inexplicable (of course they aren't, they've happened all season) - Everton don't actually suffer from a hex or a curse, they've just had a succession of defensively weak coaches.
There's probably more I'd like to write on this but I think that's what people mean when they say we need to change the style - what we are currently doing is exposing the weakest part of our team and not really allowing us to reap any benefits. Let's face it, we don't look like scoring do we, even with more of the ball! The question is whether you think Lampard will recognise this too, and look to go back to how we played against City - I think he's either too naive or too arrogant to recognise that's what needs to be done.