Self assessment enquiries

Enquiries by the Taxman into self assessment tax returns generated, on average, an extra £7,778 of tax over the last year. This is a big jump from the year before when the average take was £4,527.

Could this be something to do with the fact that tax inspectors now get a commission based on the extra tax that they find? Also, many of those targeted do not have accountants working for them and may be susceptible to pressure exerted and games that the Taxman has been known to play.