2 Questions about 301 Redirects

[BrianJGomez]

So I have a couple of questions about 301 redirects:

1. Do Google penalties EVER pass through a 301? I've done 20+ domain 301s in the last year and have yet to see it happen, but the other day I read a an article (or maybe it was a QA post?) that suggested doing 302s to avoid transferring penalties. Has anyone seen any authoritative information regarding this?
2. I 301'd a domain in February that another SEO firm had built a lot of spammy links and I began building contextual links for it at a very slow rate (like 10 or so a month). Within a month, my domain authority was a 26 on the new domain and my inbound links were non existent. By month 2, my links were 70k and domain authority was 34. By month 3, down to 25k inbound links and domain authority of 29, where it has settled for the last 3 months despite some really high quality links. My question (don't worry it's coming), is does anyone have any clue why my links shot up so quickly and then dropped? I'm assuming the 301 links kicked in and then only about 45% ended up 'sticking'??

Thanks in advance

[kchandler]

Do Google penalties EVER pass through a 301?

Yes. 301 redirects make sure end users, search bots and link equity are passed to the new page. It is true though that not all link equity is passed with a 301, however good or bad it is passed. I have found this out with my own testing with clients as well as a few post i found on SEO round table and Google groups.

Does anyone have any clue why my links shot up so quickly and then dropped?

Where you tracking your external links use OSE? If so they crawl a different amount of domains and URLs each time they update their index so chances are you are looking at different data sets each time.

[Doc_Sheldon]

Brian-

1. In a hangout two or three months ago, John Mueller said that 301s can pass a penalty. Whether or not a 302 will do so as well, I don't know, but I'd be hesitant to bet on them not doing so. We've never tried redirecting in a penalty situation. I have spoken to some colleagues, however, that say they've had clients come to them that had 301'd and the penalty showed up on a new domain shortly thereafter.

2. Did your drop-off happen to coincide with a Penguin update? At one time, Matt C. had said that the results of cleaning up a link profile wouldn't really come into play until the next update (for an algorithmic slap). But others and I have seen instances in which that seems to no longer always be the case - 2 weeks to two months, with no update, is showing evidence of removed dampening.