"I think we all agree the Dens Road drain issue now looks like a lie. Your theory on compaction and thatch would be resolved by removing the top layer which has been done a few times over successive seasons without effect, in fact it seems to have worsened over the last two to three years - so that's total *******s."
I think the pitch needs more than skinning off the top layer. A sample should be taken that will show the depth of any compacted area, this can then be removed and re instated with suitable free draining mix of soil/sand to help draining and root growth.