Peter, Just a thought but I was at a TRL presentation the other day and was amazed (as where many others there) that the time that a driver looks at objects in their field of view and reacts on them is an average of .4 of a second (if I recall correctly) so perhaps we should be wary of a .25 second lag. Just a thought (I'll just doze of in the corner now) Tony Sharp ********************************************************************** This email and any files transmitted with it from South Gloucestershire Council are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify the South Gloucestershire Council Postmaster at the address below. This footnote also confirms that this email message has been swept for the presence of computer viruses. postmaster@xxxxxxxxxxxxxxxx ********************************************************************** ----------------------------------------------------------- A message from the TCUG mailing list. For information about the list visit //www.freelists.org/webpage/tcug