Secombe always taught use of the integrated range charts that start on 3-3 of the manual.
No-one else does this because they don't have these type of charts for 1eng INOP, low altitude cruise etc - so it is impractical (so the theory went) to teach the use of two different types of chart.
i'd be willing to bet that Secombe has rejigged answers with the integrated range charts.
Has anyone who recently failed used the integrated range charts?