Hello,
It was long time ago that I looked at Mail.app - I'm totally pro apple but i find mail is "to small not worked out at all".
So many functions for automation and customizing aren't there...
If you watch the rules for mails... so little possibilities.

But a few weeks ago - I need Mail for automation my E-mails.
Want to applescript my workflow and then it's better to use mail.

But I had troubles with the attachments. (.txt)

I knew there where in the past a lot of problems with mail and attachments... (.eps and .ps where real mail problems)
That's one of the reasons I changed my email software.

Now today

I'm using Mail Attachments Iconizer 2.1.4. and without any problems.
It's even stronger for me... Without Mail Attachments Iconizer I don't use Mail !!! Then I can't do anything with it !!!

Clean install - easy and very clear to me.

I can choose what to do with the attachments... These functions aren't build in mail and YES it should be. Also possible to say show or not show from the file size. nice.

I see one smart post in the comments and that's about the terminal.
OK that's also possible but I like to do it with an interface in mail and that's what's Mail Attachments Iconizer is about. No terminal needed and it does what I need. not more / not less

Will give more feedback when I have done more with mail and tested all functions of Mail Attachments Iconizer.

Keep on the good work Adam !