That is correct. I believe that some people believe you can get an astringent flavor from steeping in too much water. That temperature and time are perfect. You don't want to boil grain, or really let it get into the 170s or above.
While looking into my brewing water use, I stumbled upon some advice for steeping that I applied to my next brew. It has been cut and paste a few times, so I will go ahead and post it here. Original credit to user Saccharomyces:
I was talking with Chris Colby (BYO editor) a few months back about his method for extract/steeping grains. We were discussing your very problem which is very common -- 99% of brewers will get to the level where you are now with extract/steeping grains and think they have to go to AG to make better beer. Fact is you don't, Chris only does AG batches with a brew buddy. He has been doing extract for 20 years and he makes some GREAT beers. Here's the Colby method:
- Start with 1 gallon of Campden treated RO water and 1 tsp of 5.2 pH stabilizer in the kettle. Stir in 1 lb of dry extract while heating to 165*F. At 165*F remove from heat. Drop in the steeping grain bag, tea bag it to get the grains wet and let it sit 30 minutes. Steeping in a small volume with pH stabilizer and extract keeps the pH around 5.2 which will prevent extracting tannins from the grain husks, which is the most common off flavor in extract beers.
- Drop a strainer over the pot and move the grain bag to the strainer. Run your top-off water slowly over the grains to rinse them until you get to your desired boil volume. Stir in 1/3 of the remaining extract for a partial boil, or 2/3 if doing a full volume boil, and bring to a boil. Add your bittering hops.
- With 15 minutes left in the boil, add a whirlfloc tablet, yeast nutrient, and the rest of your extract (do this off the heat so you don't scorch of course!).
- Stir continuously while chilling until the wort drops below 140*F. Chris uses an immersion chiller in his sink and then moves to an ice bath until he gets down to pitching temp. I already gave you my method, while more hands-on it works too.
Give his method a try and I think you'll be amazed at the results.
If you didn't do all that, you will probably still be fine. Consider it a control batch before trying the Colby method.