David, personally I think if you 'jam' someone because he's only using brute force to throw you, you are ok. Unless of course you're doing it to a beginner who doesn't know anything better. But it depends on nage really. If he's not interested in finding the aiki solution in his training, then don't bother jamming his technique, just flop like an aiki bunny. Saves you a lot of grief in the end.
Yes, I absolutely agree with you, especially the grief part.