That is valid in the context of general training, but if you train for NT or especially home-grown then you can't really choose your player's level of RB, can you?
And also - why is SB bad for guards?
BBB: 2 (S37 S38); Top tier: 7 (S35 S36 S37 S38 S39 S41 S63); Cup: 9 (S25 S35 S36 S37 S38 S39 S40 S41 S61)