with the 531 ronaldo would first have to get past the lb then the lcb. if both players are beaten ronaldo would still have 2 cb's and a rb to get past or blocking space for rooney etc to run into.
also the attacking player ,lm , is left as an optimum attacking option.
Like I said, teams attack down the flanks now. So Ronaldo wouldn't be attacking on his own as almost always his full back would be there with him (this is an area we need to improve big time btw). If you look at the top two this year (Chelsea and Man Utd) not to mention Barca et al, they play 4-3-3, and they play it because of its flexibility. Teams often play very different formations when in posession and when out of it. So 4-3-3 in attack becomes 4-5-1 in defence. To make the system work you need real flyers on the flanks, capable of getting up and down all day, plus players in the middle capable of keeping the ball, either with feet in midfield or holding up in the centre forward position.
So lets say in attack Ronaldo and Brown are there for United. Baines is the wing back and Lescott goes over to help out as its 2 on 1 otherwise. Rooney's the centre forward so he's marked by Yobo. Scholes drifts in and is picked up by Jags. Assuming you don't want 2 on 2 at the back Carsley would drop back as well to help out. Anyone picking up Anderson? Your 5 defensive players would soon get over-run.
if the wide midfeild are pinned back helping out the full backs in a 451 , and adding to that carsley being a defencive midfeilder , then it would mean 7 of the 10 outfeild players would be in negative positions , ie defending. leaving only 3 outlets for attack.the striker will surley be isolated due to lack of support.(ring any bells ?)
Like I said, full backs are the key to modern football. If you look at Evra for instance, he's a fantastic athlete and can get both beyond his winger and back to his defensive duties in no time. With the holding midfielder sitting to slow down any immediate counter attacks. This season we've often had a centre back at left back, and a duffer at right back. Liverpool are similarly weak at full back.
imo the 3cb's are comfortable enough on the ball to play 532/5311/5131 and would have many more options around them to play the ball out of our half rather than resort to a hoof ball .
They are, but who would they pass to? If you have a defensive midfielder then he's the first port of call. Carsley hasn't been up to that job thus far and a change in formation won't change that.
That pretty much sums up my request for the summer, some new top notch full backs and a world class holding midfielder that can kick start attacks as well as kick start opposing players into the stands.