Do DoubleClick DART Tags degrade link juice to your site?

[Yun]

My site has a content distribution agreement with Yahoo Finance for the daily articles we publish. It's delivered to them via XML, and while we don't have in-line links within the article, we do have

1. Clickable Logo image

2. Standard language at the end of the article with a link back to our registration page

We use DART clicktags (http://ad.....) that redirects to our homepage combined with ?src=YahooFinance&affiliateId=77 query strings that are generated by these clicks to measure registration and sources

My question is twofold.

1. Are the doublclick clicktags hurting the valuable linkbacks from Yahoo Finance for picking up our content

2. What should be done with the query string extentions once people land. We still want to see that data in our Google Analytics, so is a rel=canonical the appropriate solution?

[miloszpekala]

This is exactly  what I'm trying to determine as well.   My initial findings tilt toward very low seo value but haven't found a definitive answer.