Driver dealt with for insecure load

? please explain exactly what the issues where here “make sure you know what the labels on thw straps mean when you use them”?
1) what is a thw strap ? is that a typo for the or an abbreviation for throw or through ?
2} do they mean using the straps like that on the wheels is not on the labels of tie down straps ?
3) all the labels usually give is the maximum “force or extra weight” applied by the strap to the load / vehicle contact point which through the coefficient of friction for the materials gives the resistance to motion of the load to vehicle with the strap at 90 degrees to the contact . Applied math has to be used when the straps are at other angles which is not given on the label. eg a strap rated at 5000 kgs angled at 90 degrees to the contact point gives 5000kgs equivalent to the resistance of the load to move by friction via the static coefficient of friction of the materials at the point of contact under braking and acceleration against the mass of the load. So if the coefficient of friction for the materials is 0.5 (area of contact plays no part surprisingly) a 5000 kg strap at 90 degrees to the contact point gives 5000 x 0.5 =2500 kgs of load movement resistance in forward, back and sideways resistance. Straps at different angels only give the COSINE of the angel of the strap to the point of contact (a non linear number ) which always reduces the effect of the strap. The law requires loads to be restrained only by a % of their mass backwards and side wards with 100% forwards. In the picture given account has to be taken also of the angle of the deck ( uphill from rear to front reducing load restraint by the cosine of this angle ) and the fact that the step frame trailer appears to be in contact with the rear of the load (headboard contact not shown?) one would assume the handbrake on the load would be applied also this is not shown.however the load does appear to be in contact with the tailboard / ramps)