"it shall be unlawful for any person knowingly or intentionally ... to manufacture, distribute, or dispense, or possess with intent to manufacture, distribute, or dispense, a controlled substance ...." 10 . In this way, § 841(b)(1)(A) is quite unlike the sentencing guidelines. When applying the guidelines to a defendant convicted of participation in multiple drug violations or in a drug conspiracy, courts are required to aggregate the amounts of drugs for which the defendant and his or her co-conspirators were responsible. See USSG § 2D1.1, comment. (nn.6, 12). Section 841(b)(1)(A), on the other hand, requires a sentencing court to consider separate violations of § 841(a) without aggregating the amount of drugs involved. Accord United States v. Mergerson, 4 F.3d 337, 346 (5th Cir.1993) (<HOLDING>). 11 . Although the jury found Winston guilty
holding that any error by a district court in applying a sentencing enhancement is harmless if it did not change a defendants total offense level holding that when the indictment charges that a certain minimum quantity of drugs is involved in the offense proof of that quantity is a fourth element of the offense holding harmless any error in district courts drug quantity determination where undisputed quantity of drugs was enough to place defendant at the base offense level calculated by the district court holding that a defendant who stipulated his drug amounts prior to sentencing waived his right to appeal on the issue of the drug amounts holding that when applying guidelines it is proper for sentencing court to use amounts of drugs discussed in negotiations in order to calculate base offense level whereas when applying  841b1a mere proof of the amounts negotiated would not count toward quantity of heroin applicable to the conspiracy count