I stand corrected with regards to the windsock. You are correct in the FAA standard regarding the 15 knots. The Australian MOS does not specify a wind strength, rather it now specifies the dimensions of the windsock and a fabric type that is suitable. It used to be that windsocks were 15 or 25 knots depending on the fabric used.
In terms of the strict liability law, if you took off with the GW indicting over the MTOW of the aircraft, you would be guilty. I do not believe the ‘reasonable mistake of fact’ defence would not cut it in those circumstances.
This whole thread regarding ‘oztranauts’ is enlightening about the standards to which we hold ourselves, and also judge others by - I had a major carrier in Oz report visual a few years ago to approach going into Melbourne. The controller then gave him as traffic to me and told me to maintain my own separation. I replied that would be hard as he was going in and out of cloud ro which the approach controller then applied positive control to us both The problem here was that the other pilot had put the separation of us both at risk by not applying the rules properly.
There are times when breaking the rules are acceptable, but it is not to try and take off 200kgs overweight according to a GW indicator, nor to accept a landing a few knots outside the certified limits of an aircaft’s limits, particularly when there are other options. Being safe, being legal and being practical may not always give you the same outcome, but there is always a right choice.