I agree with about 80% of what you've said

Indeed Frank was the first one that pointed me towards old Lesser, and then I had the chance to experience it directly. I have suits (both by Frank and others) on both pre and post Harrisons, and they are both great, but you can appreciate the better quality of the pre H one. Every tailor I've talked to on the subject gets nostalgic about the old cloth.
Also agree on hot and humid v winter. For London weather, there's just no comparison. The only suit I have cut from 8/9 oz Lesser is great, but not the coolest one to wear for meetings in Miami. Then again, I would probably go for Fresco/Finmeresco etc for hot and humid weather anyway.