Bulk legitimate email: Can I predict liklihood that the outgoing messages will be wrongly flagged as spam?

Question

The recipients represent a wide variety of academic institutions and business organizations. Many use free email accounts too, like gmail and hotmail. There are several thousand addresses in the distribution list.

Seems some people on the distribution list received a recent sent email and some had it flagged as spam. I know there are guidelines made available, like these at gmail, for successfully navigating spam filters. I know this not an uncommon problem.

I am not looking for an iron clad guarantee here, but I would like to optimize the result in terms of maximizing % email messages received. How do emailers test this prior to sending?

Is there some sort of destination to which one can send an email that will process the message with an array of filters and provide a report on percentage flagged as spam and percentage delivered?

I understand that a tool like this would greatly aid an evil spammer, but I'd like to assume benevolence for the purposes of this question. While asking all recipients to add the "from" address to their address books could help some, I'd also like to remove that from the discussion as well.

What's the best way to test a legitimate email message for "deliverability?"

Thanks in advance for your comments -

Perry
Note: If you are a misguided spammer, please look away.

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Some overlap with this question from 2008:
How do you make sure email you send programmatically is not automatically marked as spam?

and this more recent one:
How to make sure email you send is not automatically marked as spam?

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Answer 1

SpamAssasin is probably your best answer. It'll give you all the reasons why your email may be rejected so that you can fine-tune it.