I recently noticed that our backlinks had jumped up significantly. I checked through, as I always do, and noticed that a blog within our industry had placed a sitewide link to us on their blog, which is great, but this same week, I noticed that our rank had dropped quite a bit for our main keyphrase. Could the two events be related? Is it possible that Google interpreted the sitewide link as a spammy attempt? Keep in mind, that during the past couple of weeks our serp's have been a bit screwey. I made a post about it last week, and now they seem like they've pretty much stabilized. So, it could be that during the "update" or whatever it was, we were just re-shuffled, so to speak.
A link comes to you will never hurt. You have little or no control of that event and Google knows that. So, it's not the problem here.
If you have been building backlinks with the same anchor text as the blog posted, it is possible that it tipped the balance in terms of the % links with the same term pointing at the same page. This could look 'manufactured' to Gooogle which may affect your SERPs for that term. Make sure that your back links have alternate anchor texts to avoid the problem
Even though it's not entirely likely that this is the result, he is correct in saying that in theory that could be why. It's good advice not to use the same anchor text, unless that is that your anchor text is your actual site name (URL) in which case it will not be a problem. Even though as I said it is not *likely*, it is possible what he says so in the future switching that up and using other anchor text would be a good idea. probably more likely is it is just a routine fluxuation, especially if you say your SERP's have been fluctuating lately. Google has been all over the map lately, you are not alone.