"Mail Merge" email notices -- can I?

Is there a manual or reference for how I can add "Mail Merge" and logic to email.txt templates?

For example, I've added a field in aMember called "comments" -- and I'd like to copy and paste these "comments" in a follow email...

... At the same time, if the new member did NOT leave a comment, I don't want to copy and paste it.

Here's an example of a new member leaving the following "comments":

Comments:
I'd like to know more about SEO and email marketing

Since the "comments" field is populated, the followup email might go something like:


Subject:
Welcome to our membership site, Pat

Message:
Thanks for joining Pat... I'd like to invite you to ask your question in our member's only forum. Here's what you asked:

I'd like to know more about SEO and email marketing

[Rest of autoresponder text goes here.]



At the same time, if Pat didn't leave a comment, an if/else was display something like:


Subject:
Welcome to our membership site, Pat

Message:
Thanks for joining Pat... I'd like to invite you to ask questions to your most pressing marketing needs in our member's only forum.

[Rest of autoresponder text goes here.]


Extra credit: It would be great to know the if/else syntax to check the number of characters in the "comments" field -- for example, I wouldn't copy and paste a comment like:

Comments:
You're a jerk

... In the email -- so my if/else statement might only trigger if the comment field was at least 12 characters.

Can you help me with this -- I would have asked this at aMember support, but I know this feature would be helpful to just about every aMember subscriber... when I used logic with my old membership software, the response was much higher than without.

Tip:At the same time, don't believe the gurus out there who say adding someone's name increases response... that's not always true.

aMember mail merge

Okay, I'll try that... but can you help me with the if/else to only display if the field has at least xx characters?