klem,
Don't waste your time with a charlatan, generally you are doing just fine with the tests.
There is plenty of good testing manuals available freely in the net, IMHO the best one is the USAF Flight Test Engineering Handbook, available from Scribd:
http://www.scribd.com/doc/19204672/U...ering-Handbook
It's a large file, over 700 pages but worth to read. As example the correct way to test the critical altitude can found from the section 2.5 (p. 382->).