The FDIC has long recommended [1] mandatory vacation blocks as a fraud-detection tool:
It is the FDIC's goal that all banks have a vacation policy which provides
that active officers and employees be absent from their duties for an
uninterrupted period of not less than two consecutive weeks. Such a policy
is considered an important internal safeguard largely because of the fact
that perpetration of an embezzlement of any substantial size usually
requires the constant presence of the embezzler in order to manipulate
records, respond to inquiries from customers or other employees, and
otherwise prevent detection.
Yep - don't know about the rest but my former employer, Morgan Stanley, has a mandatory vacation policy (MVP) in place. You must take two consecutive weeks off per year.
[1] https://www.fdic.gov/news/news/financial/1995/fil9552.html
[2] http://www.marketplace.org/topics/business/easy-street/credi...