It surprises me that SAS does not sign each flight. I certainly do and everyone else I know does the same thing.
(sic)
There is no requirement whatsoever for this in the UK at SPA level. I understand that it is an FAA requirement, so perhaps people who have attended FAA schools have brought the pointless habit back with them from the USA.
Apart from FE signatures and FI SEP revalidation training flight signatures, I wouldn't expect to see any other FIs' signatures in UK personal flying logbooks.
I really fail to see what value your comments add to this thread, bose-x....