The TIP ETF dropped >10% in October/November 2008.
What might work for you is I Bonds. You do have to hold them a year before you can sell (so you have to keep other emergency funds available until a year has passed), but I Bonds do give you absolute preservation of principle as well as inflation protection and some income (assuming we don't have significant deflation - in which case you will still have a positive real return).
Others have already stated this basic thesis in different ways, but buying TIP as an emergency fund, if you expect preservation of principle, is wrong.
TIP NAV could drop 10-15% from here. What are the odds? Who knows? The point is, this isn't a safe investment for preservation of principle, even if he inflation adjustment helps.
I just looked at the MINT fund on the Pimco site. Here's my take, for what it is worth.
"PIMCO Enhanced Short Maturity Strategy Fund"
"Estimated Yield To Maturity: 1.24%"
"Expense Ratio: 0.35%"
It is getting slightly higher returns than a typical money market fund by taking on slightly more risk. It is not FDIC insured though. You can lose money.
An online savings account that pays 0.89% (1.24% - 0.35%) or more would seem a far better choice for smaller investors under the $250,000 FDIC insured limit.
ING Direct pays 1.25% right now and is FDIC insured. You can set up an account online without even talking to anyone.
It's also easy to link it to an existing checking account. Moving money back and forth is free.
Ally's online savings is paying 1.49%.
The best deal for rates I have found are the Rewards Checking accounts offered by local banks. Some pay up to 3.5%. The catch is you have to jump through hoops to get this rate. The biggest hurdle is that 10-12 debit card purchases are required each month.
that is not an answer that is an observation.
That happened as inflation was FALLING therefore, tips at that time were not the place to be.
Will Fed raise rates?
Is inflation going to rise (and yes, if they do raise).
When you see rates falling/inflation falling that is when you get out.