Thanks Michael! Good question. Chay Hathway/ FA Refereeing- one for the referees to respond to perhaps?
Advice I received from the my local FA is as follows. Hope this is useful for others
"The answer to your question is, this is down to the referees discretion of incident at the time. The advice we give to our referees around shielding is, arms out to create space is fine however when there becomes contact with an opponent, such as a grab or holding offence and/or arm to face. The referee is within his rights to award a freekick."
Absolutley yes you can, a great skill to have, your area becomes so much bigger by using your arms.
By learning how to turn your back, or side on when running with 1 arm out giving as much distance from the ball to your opposition is a great tool to have.
You dont need to grab an opponent your just using your body to provide that space.
The opponent will more than likely grab your players arm.
I do a practice with my u8's where 1v1 no ball about a 3mtr square space, the attacker has a tag on his front and the defender has to try to get it its great for coaching protecting the ball in possesion and for defenders how can they manoeuvre to win the ball