This snippet came from an email I
received this morning in regards to encouraging folks to whitelist you.
To their point, while results may not be phenomenal, the cost is next
to nothing. And pay attention to all the locations you can encourage
folks to do this at. Implement it - it's worth it.
"Where and when do you encourage subscribers to add you to their
safe lists? At opt-in, on the confirmation screen, in your welcome
email and in every email thereafter. While only a small percentage will
comply, it costs virtually nothing and yields a group of subscribers
with dramatically improved delivery or image rendering." - MediaPosts
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