James, I see your point, but I disagree. You are correct the single item analysis instructions limit you to a 2 month cushion on any one item §3500.17(d)(2)(C)]. I'm not reading RESPA thoroughly to try to prove you wrong, but I disagree this is the intent of RESPA. The point of the aggregate analysis is that you list everything (just like you did with the single item analysis) and take the difference between it's total and the sum of the single item analyses.
If we use your logic, you could use a 0 cushion on every single item analysis and then use a 2 month cushion on the aggregate analysis. This would really throw things off.
I challenge you to find one escrow calculator that will meet your understanding. You indicated you were using ours and it didn't match up to your understanding. The FDIC also has a calculator & I believe the FRB has another. I don't believe any of these will allow you to change the cushion as you indicate.
You've got an argument, but I believe it misses the point of the law. There are many places in RESPA that aren't spelled out well. You have to read the preambles and other guidance that has been issued. You can continue to debate this with your examiners, but my professional opinion is to give it up.