questions on *date and *export

[Thomas Holder]

I have two questions on the svx data format:

Manual says that *date is only valid at the start of a *begin/*end
block. But a survey can be split over several days. I tested this and
placed *date commands anywhere in between data lines and it works fine
("Color by date" displays correct), but will it also work with future
survex versions?

Why is it necessary to export points? Is there any disadvantage in using
"*infer exports on"?

Regards,
  Thomas