No hawk37, you're not talking nonsense, what you say is perfectly valid.
Dani, you state that "it might be in the 1% range on a big jet, it's much more on smaller or medium jets". Our airline and it's subsidiaries operate aircraft from the A380 down to the Learjet 45, that's got to be some kind of record of weight range in one company. I have access to all of the AFMs for all of these aircraft, and for the Learjet 45, the Delta gradient between V2 Gear UP and V2 Gear DOWN is 0.89%. The Learjet is definately in the SMALL jet bracket, but with similar figures in this area to the "heavy metal".
At the end of the day it's type specific, but consider this - The maximum Delta tolerable for any twin jet would be 1.59%, as 1.59% subtracted from the minimum required 1.6% Net gradient leaves a mere 0.1% to satisfy the "positive climb in the first segment" requirement. Any aircraft with a greater than 1.59% Delta would require more than the regulatory requirement in the 2nd segment, and would not be economically viable!
Regards,
Old Smokey