Im pretty sure we discussed this to a certain extent on the offsite at some point didnt we?
I mean, something like this would need to be talked about between first the NT and U21 managers to figure out whats best.
I think this was discussed as a lot of MVP players, since very few can make the NT any more, were going to be trained towards the U21 team. While the HOF and ATG( very few) were trained towards the NT. As for SFs though, I think thats where more thought needs to be put into it. But it seems a lot of the great SFs that make the NT, usually make the U21 team as well.
This can be a potentially good idea to keep the U21 great, while still improving the NT though.