A good goalie and a good defense will keep you in games but you need consistent scoring to succeed. Either from a mid or a couple of strong finishing attackers.
I know there are some exceptions, but at this age, I feel like middies score 70% of the goals for teams,
Not during a game between two top teams where most of the goals are in settled play. In blowouts or games without defense, I'd agree. But if you ever watch a game between M&D, Heros, Aces, YJ, BLC, and a few others, there are very few transition goals and lots of settled play goals where attack is highly involved.
