Thank you for the fast and informative reply David, and thank you for the link.
My "regular" AME in Singapore also disagrees with the 180 target, considering them ludicrous and dangerous.
No, I don't feel any light headedness or vertigo when suddenly standing, even though the lowest ever recorded BP for me was 102/68.
It must be remembered that in Singapore in the 90's, the Civil Aviation Medical Board mandated angiograms (which carry a mortality risk) for perfectly healthy pilots, it was all part of a survey you see ...........
Further comment welcome.
Regards,
Old Smokey