Possible Clues:

• Lower boom to make working space
• Enough scope to function
• Push Othello, say, to make a comeback in play
• Enough space to work or move in - flex arm
• Space to manoeuvre something lifted in pub
• Enough space for drinking?
• Adequate work space
• Space to manoeuvre - for arm-joint
• Lower boom awkwardly to provide sufficient space
• Why would the Moor return to that joint, even if there's enough space?