The "Three-Rookie-Defenders-On-The-Field" Tactic

[Sparxx]

What are the pros and cons of this? Right up until now I've had 4 premium players in my defence (Goddard, Gibbs, Hartlett and Heppell) but I've seen more and more teams being posted that have 3 premiums and 3 rookies. 

I decided to give it a go and discovered that now I've been able to fit Pendlebury in my midfield alongside 4 other beastly midfielders, as opposed to Moloney - which will obviously get me more points - but I'll lose out in defence (Pittard has now become my 3rd rookies, and could do okay, but how will he score compared to Hartlett)? Overall though I should get more points.

Have I overlooked anything? Whats everyone else's opinions on the matter? Pros and cons of this system?

[BillyBass]

To me it's a matter of cash generation. This year all the good rookies are in DEF and MID, with practically none in RUC and FWD. I've gone with 3-0-5 DEF setup and that has allowed me to load my fwds and rucks with premiums.