Well, I did a bone head move and overtorqued my tranny drain plug bolt by 5 foot pounds which is nothing to fret about, but overtorqued none the less. I've overtorqued bolts and have had the bolts shear off, (bad old torque wrench and thankfully not on this car), new torque wrench = new hotness.

But, I'm wondering, how much variance do you suppose honda and other manufacturers give for torque specs. I mean, you can overtorque the oil pan drain bolt by a little and be ok and you can undertorque and it'll be ok.

 

How much you can over-torque something depends on what that something is. The oil pan bolt OEM torque is, in many people's opinion, already overkill. This is because the threads in the pan itself is very short. However, 5 ft/lbs over is not a big deal. Next time you take it off, I would suggest that you change the washer for sure. If you used the correct torque, this washer can be used several times.
If you had a steel bolt going into a deep steel thread, you might be able to double the torque and still not break anything, but this is not recommended because even though it doesn't break anything, it does over stretch the threads on both components and once stretched to that degree, will never come back.