Вот копия ответа уважаемого господина Джорджа Споффорда (George Spofford)

It depends. Mostly, they will get calculated on the client
side. However, depending on settings including the Large
Level settings and Execution Location, they can sometimes
be executed on the server as well. As far as we can tell,
if a calculated member is involved in evaluating which
members of a "large level" form the axis of a query, then
that calculated member can be evaluated at the server.

There are some things you can do which force the
calculated member to evaluate at the client tier, like use
an external function that isn't registered at the server.


НЕУЖТО calculated member чтоб 100% выполнялись нужно использовать свои внешние функции???

Разница в том, как пишут, сколь информации будет тянуться на клиент, а то если долго и много будет обрабатываться, то начальство не поймёт и выдворит с "моими" нововведениями...