[Dovecot] is it necessary lmtp and director to avoid index corruption in mail delivery?

[mailing lists]

Hello all,
If I have several postfix/dovecot-lda boxes with shared nfs storage, how 
director helps in this scenario? is it necesary to use lmtp instead of 
dovecot-lda?


With postfix/dovecot-lda boxes incoming mail happens at the smtp layer but 
director redirects are working in the lmtp/imap/pop3 layer.