Thermoquad tuning on 318

66fs,
Yes should 'work perfectly'. This carb or any other carb for that matter is only going to work perfectly if all the read adjustments are correctly done. I listed a few things that I know can cause the OPs current problem.
Nowhere did I say to throw parts at the problem. I have a box full of defective AV dashpots that have had the diaphragms stiffen up over time. Time? If original, these dashpots are over 40 yrs old. They cause strange problems. Rubber perishes over time.