Thinking about DIY debt settlement

Long story short- I have just under $20000 in CC debt with 6 different creditors. I enrolled with a debt settlement company in July 2009 but am seriously considering the DIY debt settlement route. I am pretty confident in my ability to have tough skin, which I know is one of the biggest things to keep in mind while doing it yourself. I do, however, have some questions:

1) Chase called me directly and offered 50% settlements on 2 of my 3 accounts with them. I told them I wanted the offers in writing but the lady (who did not sound like she knew what she was talking about BTW) said they can't mail out an agreement letter until I agree to it (doesn't make sense to me). I am going to call them again this week to see if I can talk to someone else and see if I get a different answer. My question is- if they send me a settlement letter/agreement in the mail with all the terms etc, how long do I have to mail them back an acceptance? I have yet to settle on any of my accounts so I have no clue how the agreement process works- do they send me an agreement or do I send them something?

2) My BOA card has gone to Redline Recovery and my HSBC card has gone to United Recovery Systems. I sent a debt validation letter to both today to make sure they are authorized to collect on the debts. My question- assuming the validations come back and they are valid debts and are authorized to collect on the debt, do I just communicate with Redline and URS directly then regarding setttlements? So I end all communication with HSBC and BOA? (which neither have ever called me on the phone directly, I only get written correspondences)

3) My biggest reasons for using a debt settlement company to settle my debts is twofold. For one, I have really bad anxiety and so if I had to answer every phone call that came in and talk to nasty debt collectors, I'm pretty sure I'd have a nervous breakdown. Second, I am new to this and have no clue what I am doing and what I need to look out for (legal stuff, what to get in writing). However, since I've been in the debt settlement program, I've accured funds in my settlement account but none of my accounts have settled (my debt settlement company received one offer from Chase for 58% of the balance, which I rejected). I've started checking this forum religiously for advice and am also reading up on debt settlement books out there also. So I'm gaining confidence in myself to do this and honestly it'll save me hundreds each month by not paying a third party for it. I just need some guidance though.

Thanks!