The best thing to do is talk it out. Riot said they prefer Pick order over call order for various reasons. Mostly pertaining to how long it takes to connect. But if you really talk it out with your teammates and figure out optimal lane assignments, that would be better than either call or pick order.
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5 roles, if the guy doesn't want to support someone else can support.
Keep in mind that people actually want to win. People don't want to support because they can't solo Carry the game from said position. And that's why no one wants to play support.
I'll play support. Mostly because I care more about having fun rather than winning. And if I want to Carry as a support. I just pick Either Karma or Morgana, and take over lane if the ADC fcks up.
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Elo/mmr shouldn't really be an excuse for a person not to learn every role to a certain extent. At one point or another, I think ranked bronze players don't simply because they are unaware that they have to. No one really explains to them the necessity or utility, and they just never find out.
The funny thing is, I commonly Use Teambuilder to practice a variety of roles. But I chose roles base on how likely I am to get into a game. So I have a lot of Practice with Support, ADC, and Jungle. And Ironicly those are the roles I chose to master first in that exact order. I started support because Sona was my first champ that I really liked. I went ADC afterward because I already knew a good deal of bot lane mechanics. I picked up Jungle this season after the item changes scared people away from that role, and I filled a vacuum.
I never troll nor intentionally feed. But if I'm forced to play solo lane, All warranties are off.