USA-based Zigon Performance Group have some interesting suggestions recommended for that section on evaluation/appraisal forms set aside for additional comments which is often left blank.

You might like to try using the following:

'this young lady has delusions of adequacy'
'works well when under constant supervision and cornered like a rat in a trap'
'some drink from the fountain of knowledge;he only gargled'
'this employee is depriving a village somewhere of an idiot'

Although using some of these may be tempting (and there's more humour available at www.zigonperf.com), Zigon are also offering some more serious stuff which is probably of more practical use where managing performance is concerned.

The Group offers a number of systems for measuring performance measurement for hard-to-measure work and teams. The US 'flavor' of the site needs to be taken into account, but there are competency grids available for a number of different job descriptions which could be equally applied to UK-based jobs.

Zigon also offer a consulting service, how-to articles on performance management and links to other measurement-related websites.