Well I feel like an ass, who would have thought you guys would have been talking over here about the same damn thing for days. Note to self read every trending thread before posting.
Ok well I have stated my 2 cents in my seemingly redundant thread but I will breifly summarize here so I am on the record:
I have 2 bikes near identical geometry, same wheel size, and same tires. One is far more stable at higher speeds much less twitchy feeling and much easier to ride with no hands (i dont usually like to grandstand like that though). The only real difference i can find between the two is the Mechanical steering trail, the smoother one has 45mm of trail and the twichier one has 35mm of trail. All the info I have found online says that most road bikes try to hit the 50mm-65mm trail number.
I should also state that on both bikes though they are both 20" wheels they have very heavy tires (770g maxxis hookworms) which would give them much more rotating mass increasing the inertial gyroscopic effects though I havent notice any significant stability effects on the bike when swapped for my schwalbe kojacks which knock about 1 pound of rotating weight off each wheel.
On a side note I am upset that many bike manufacturers these days and pretty much all folding bike manufacturers don't provide geometry infomation about their bikes. At least armed with a little info you can make some intelectual comparison before you put so much effort into finding a place that you can test a bike or in the case of folders where many times you have no choice but to buy it online.