On 2007-08-01 11:56:14 +0100, Owain said:

Andy Hall wrote:
One thing which worried me slightly (from the link above) is mention
of erasable marker tips ....
Yes, Really it's not essential for operation. When you have the
device in position, you press a tit and it puts a mark on the wall for
you. This is helpful for Americans who are still working in
deprecated imperial units rather than following the Napoleonic Ideal.

Why would the measurement system make a difference? Surely it's so
Americans can have do the job one-handed with their gun in the other?

Owain

HD sells contractors' calculators that perform arithmetic on 32nds and
so on. Such is the ridiculous extent of non-decimal measurement.