Today, into the Mailing settings (on Org settings) you can choose between 2 options where the Tracking Image for Opens is places, and beggining or at end of the mailing.

I usually use the default configuration, i mean, at the end. (with that we expect a better metric since the mailing is open if the image is loaded, and on preview email systems is loaded only if the customer see all email, so expect is not open by accident or just a preview when the customer place the cursor onit.

But, several of my customers are force to include legal disclaimers on each communication. A very large disclaimers text... So, many of the customer do not read those disclaierms and close the email. The result: the tracking image is not loaded so the event is not registered.

So, will be a good idea take the control of the place where the image is on it. Or add the middle as option... so we can keep the good practice and don't loose several of those opens.