Rebuild Index?

We have table with lot of insert/update/delete every day. High OLTP application in 11g R2 on Linux.

To gain performance my teammate recommend Rebuild index.

His assumption Index size should be less than table size. Other wise we need to rebuild index.

Is that correct? Want get your thoughts.

I am skeptic after Reading Asktom and Jonathan Lewis blog. Both of them claim need good metrics and it is last option.

Thanks
Karth

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