Mr. Blake is incorrect. The type of lien the IRS files is what we characterize as a general lien, meaning that once recorded, it becomes a lien on all real party the taxpayer owns in the county. It does not gain some sort of "super priority" but has as I mentioned in my earlier posting, a specific right of redemption for a brief period after the foreclosure sale that is not often exercised because of the lack of taxpayer equity in the property (the difference between the property's fair market value and the voluntary liens (typically secured loans) on the property that have priority over the IRS lien.
You can confirm my understanding of the foreclosure law as it relates to IRS liens by reading
http://recenter.tamu.edu/pdf/1110.pdf which states:
Holders of prior recorded security liens need not worry about losing priority to federal tax liens. A foreclosure on the prior recorded security interest will terminate a subordinate federal tax lien if the lienholder gives the district director of the Internal Revenue Services (IRS) at least 25 days advanced notice of the foreclosure. The notice must be sent by registered or certified mail or delivered personally. The requirements of the notice are found in 26 CFR Section 301.7425-3(d).
Giving proper prior notice of the sale does not cancel the IRS's interest. The IRS has 120 days from the date of the nonjudicial foreclosure sale to redeem the property by tendering the sales price (See Internal Revenue Code [IRC] Section 7425[d].)
Daniel