Sending html email and editing the server config

I’m learning how to create multi-part emails with NotesMIMEEntity. One of the suggestions I saw somewhere said to change a parameter in the config document. Specifically :

Configuration\Servers\Configurations edit configuration Under MIME Tab\ Conversion Options\ Outbound\Message Content

Changed the Option to “Convert from Notes to Plain Text and HTML”.

Is this change absolutely necessary to send this type of email?

Subject: *No. Once it is in MIME, it should usually be left in MIME.