Originally posted by dbbyleo

My common sense tells me corruption at the bit level on the primary database would have NO affect the standby because the standby applies changes to itself in a LOGICAL manner, meaning it applies the transactions, not copy physical media to itself....(except for the actual archive logs it needs to apply transactions from)
Your common sense fares you well young padowan!! )

Basically, what Oracle are getting at is that the delaying of the application of logs by implementing a manual process allows you to correct a user error before it gets applied at the standby site.
There are various ways of setting up the 'managed' standby database, but some configurations mean that the transactions are immediately applied at the standby site, before being committed locally. In this situation any user error is propagated.
In my mind, you would correct it locally, and this correction would then be propogated across again!!
The main purpose of a standby site would generally be disaster recovery, in which case you want it as up to date as possible.

Brgds,

Andy