The last decade SAF averaged 50-60 millions spent per years on transfers. Seeing us signing Shaw and Herrera just makes me wonder how our team would look if every year we bought two world-class young players like Rooney/Rio rather than 6-10 smaller fee transfers like Oberton, Owen and so forth.
I think Ferguson liked his squad players.
I do agree with you though, I'd like us to work on the principle of having two players per position, one world class and one world class potential and then players that have past their peak who chose to stay with us would add further quality, depth and experience to the side.
The world class potential player would be content with a squad role from the age of 18 - 22 because they would get games but once around 22 years of age we could then sell the older world class player for quite a bit and a new young world class potential player (17 - 18) comes in.
This falls apart when the world class potential player does not fulfil his potential but then again we just keep the older player and let somebody else take his position.
E.g. We sell player in prime, 22 year old (e.g. Hazard was 22 start of season just gone) plays as first choice. An 18 year old Januzaj is the world class potential player who develops as second choice to Hazard. The 18 year old after five seasons is now 23 and becomes first choice with a new 18 year old taking his place, we sell the now 27 Hazard for £50m - £70m.
If the 18 year old Januzaj doesn't develop for whatever reason, whether it be injuries or lack of mentality, then we keep the 27 year old Hazard who will be 31 before the next 18 year old becomes 22.
If at this point the new 18 year old player doesn't become world class then we would probably have a lot of money from selling players in their prime that we could just buy somebody else around 23 when absolutely needed.
An example is Juventus.
They want to build a team that can do well both domestically and in Europe. They are well ahead of their next domestic rival therefore it makes logical sense to sell 27 year old Vidal for £50m and let 21 year old Pogba fulfil his role. Conte likes 4-4-2 so he could use the money to buy some quality wide players.
By selling Vidal they will still be the strongest team domestically however they can use the money to start building a team that will be even stronger.
Also, say they sell Pogba now and get £40 - £50m and keep Vidal, he will be worth little when 32 in five years time. On the other hand if they sell Vidal and then sell Pogba when he is 27, they will have £100m+.
World class potential isn't easy to judge though, we probably thought Anderson, Nani and Cleverley had that. But still, if you try, you are bound to get it right with quite a few players and make some serious money.
E.g. Ronaldo money could have been used to buy 3 world class potential youngsters and then add our normal transfer budget, that's about 5. If we sell a world class player for £40m - £50m, which is more realistic, added on to our normal transfer budget, we would be signing 3 - 4 world class potential players that season.