Here in Greece, where I learned English as a foreign language, there was no 'passive voice taboo' as you define it. We were just taught how and when to use it and when not, the basic rule being 'When you want to emphasize the actor, use active; when you want to emphasize the action or don't know who the actor is, use passive'. Kinda like in Sheila's example.
The examinations for various ESL certificates, however, include writing exercises such as 'formal letter', 'essay', 'proposal' etc. where it is recommended to use passive voice whenever possible. The only piece of advice about not using passive is that, if you've put 'by XXX' too many times, then you've done something wrong: you either need to omit it or to use active. (Although I can't remember whether I was actually given that piece of advice, or it's just something I realized over the years.)
See ya,
AnnaBtG.
