Connecting 'vacuum amplifier' causes hesitation off idle

Im running into this problem on my truck. The EGR system is pretty basic. It takes a small vacuum signal from the port above the butterfly on the carb and routes it to the vacuum amp, sort of a "transistor" design as it takes a small vacuum input and makes a large output by porting straight intake vacuum to the EGR proportional to the velocity of the intake. So at idle, the EGR is closed and at WOT, the EGR is also closed but that uses another system. So the EGR is only operational during cruise and low load. It lets inert gas into the intake to dilute the A/F so as to cool it in the CC, staying under the NOx formation temperature level. When it works, it doesnt do too much for driveability. when it doesnt, its hell on emissions. Either the valve will stick open causing a rough idle or the valve will coke up and NOx levels will rise and your mileage may fall as you are allowing a higher percentage of A/F into your chambers. Also the thermo valves the vacuum sources go through to the EGR are non functional when the car is cold. You can test the EGR by manually pulling a vacuum on the EGR valve itself at idle. If the car stalls, its working. newer cars use an electronic EGR valve, either active PCM or servo, or passive positional reporting or are so good they dont even need it.