The every day sign, especialy in an ancient time.
Chair, Ladder, and Car:
Every things is build and design with a weight limitation. Take a good old wooden chair, A average man of 80Kg will not break a chair by sitting on it. <PERSON> will easy break it, especialy if he give it a little swing. For a 50Kg woman the sign will be the floor wear. In ancient time floor were wood or dirt, this will be easly noticable.
For bench, once a normal man sit down, a dense one can catapult him just by sitting to fast or getting up too fast. If he goes slowly you will notice the weigth simply by the bench vribration and bend. On a bench you can notice if a kid(light) or an grown up sit on it even with your eye close.
For car and transport, this will be fun. They will either break the horse back or make a noticable shift in the car balance. Old vehicule don't have the sweet car suspension we have now. 548
And even car suspension will give them away, same test for bench close your eye and ask someone to sit next to you. You should be able to tell witch is 50kg or 100Kg.
Ask <PERSON> to use a teen bicycle for fun.
In general every they use will wear faster, If those dense live together like a familly they should not invite people home.
When we build thing we trend to build them so they can be use in normal usage. 2 people usage instead of 1 is more than -50% life time, it could be imediat failure. Things like ladder won't like your Dense Joe.
The one that don't Knock:
They also never knock on door. You can have physical expectation when earing a door knock. You will notice that the 50 Kg girl knock like a 100Kg man.
Dense Joe don't drink booze:
There is nothing that test its own inertia on object like a drunk man. Any one that even encounter a drunk Dense joe can tell: "You don't pick them up."
<PERSON> sleep on the floor:
He will tell you that it's good for hes back. But Dense Joe simply break the bed every time. (50kg+80kg)x2 in the middle of the bed. 548