Jim writes:

<<
I refer you to Advisory Circular AC-90-89 page 5-9, the Amateur-Built Aircraft Flight Testing Handbook. Quote: Caution #1 -- If the manufacturer/designer of your aircraft has not demonstrated satisfactory spin characteristics and safe recovery, avoid all types of high angle of attack flight testing and placard the aircraft: "spins prohibited.">> (This is on page 54 of the AC (Page 61 of the pdf)).

I was immediately struck by the phrase <<avoid all types of high angle of attack flight testing>>  and wondered if this included landing. Reviewing the AC you will conclude that this statement applies to spin testing only. They are saying that if the manufacturer didn't spin test the design then neither should you. A reasonable position that I agree with.  

Earlier in the same document (Chapter 5, Section 2 starting on page 45 (Page 52 of the pdf)) is a very clear RECOMMENDATION for stall testing during hours 11-20 of a new aircraft's flight testing (with details on how to avoid spins). If the FAA's position was that you should not stall test an airplane that hasn't been spin tested then the warning would appear in the stall testing section and not later in the spin testing section.

Perhaps the above quoted caution should be read "..avoid all further types of high angle of attack flight testing..", to be less confusing.

Read it for yourself at:
http://www2.airweb.faa.gov/Regulatory_and_Guidance_Library/rgAdvisoryCircular.nsf/1ab39b4ed563b08985256a35006d56af/d08fa9393154b636862569ba006f6d7f/$FILE/ATTLMVEO/AC90-89A.pdf

Regards
Brent Regan