Dab, you fools! Dab!!! Them crystals aint fentanyl and them terps aint Pine-Sol!
THC-A percentages (there is no THC in weed) before and after trimming/sifting may be completely accurate. Might even be the best of the best of the crop was chosen for label testing and the worst of the worst chosen for reports.
RDA contents and food vitamins and minerals can be inaccurate. Somewhere along the lines someone tested, say, a fresh Roma tomatoe and said it contained this and that much of this and that. Since then, multiple Roma tomatoe crops are able to be produced in a year because of breeding, fertilizing, and early harvesting. If you have ever seen a truckload of Roma tomatoes coming straight from the field, they are mostly green and forced to redden up. Those tomatoes will not contain the same vitamins and minerals as the originally tested vine ripened Roma. A more accurate nutrition label should say, 'May contain up to...'
The products I buy often have a terp breakdown. They say, up front, 'Potential.'
Carry on.