THE ROYAL MAIL is currently trialling a 'track and trace' system for letter-post - similar to that used by Parcelforce. Although the technology required is very similar, there are enormous logistical and financial differences between letters and parcels. Mail volumes average 72 million daily compared with Parcelforce's 550,000 parcels; lower postage prices also make the hefty capital cost of extending the system to letter-post a questionable investment - especially in the light of current levels of profit-piracy by the Treasury. However, the introduction of a tracking service could bring new benefits to direct marketers. It would enable delivery of bulk mail nationwide on a pre-specified day allowing, for example, a direct mail campaign to coincide exactly with a time-critical multi-media product launch - or to tie-in with other time-sensitive events, for example the Grand National or special charity flag days. A Royal Mail spokesman reluctantly conceded that trials are taking place but remained stumm about the details, offering a rationale worthy of Monty Python: 'There is only limited information, because we don't want people to know about it.'