Even none polarized pins like these have same exact issue
Yep, that web page says:
They work with 22 to 28AWG wires, though 22AWG wires with thick insulation might be difficult to fit into the pins.
Which is probably from the datasheet, and more or less what I was getting at with the "thinner insulation".
There's not a "standard" other than the manufacturer's datasheet for that particular connector. I have some Molex connectors on hand that are for 0.1" headers with 0.025" square pins, and there are two different connectors - one for 22-24ga wire, and another for 24-30ga wire. I think there's a third IDC variety as well.
Blah blah blah. The long, correct and sometimes painful answer is to read the datasheet, and any datasheets or specs that it references, and use what they say (including the $350 crimping tool designed for it).
The short answer is probably to find some 22ga with thinner insulation. 
Thanks for the link, BTW; I noticed Polulu had a crimp tool a bit nicer that the one I'm using for these, that's still within my budget.
-j