Simon Harmer urges England to recall Jack Leach for Test tour

• Simon Harmer, a South African spinner, suggests England should include Jack Leach in their Test squad for the upcoming tour.
• Harmer believes Leach is England's best option for the spin role in Test cricket.
• He attributes the isolation of slow bowlers to a lack of spin coaches in county cricket.
• Harmer calls on 'genius' Carl Crowe to enhance England's spin bowling capabilities.
• Harmer's comments come ahead of England's Test tour of South Africa this winter.