Andy, I was being way over the top for no good reason, sorry!
It’s because I don’t understand! I keep seeing the bendy downtube thing, I always thought it was originally there for shock clearance on full sussers, then it seemed to appear on bikes where the shock was nowhere near the DT.
I would have thought straight lines would be better from a design position – weight, strength, cost (and consequently, form through function aesthetics) – wherever possible unless there was a reason why not: shock clearance, heel clearance, tyre clearance, compliance characteristics. But I don’t get the reason for a bendy tube at the bottom if there’s no shock to clear.
Is it something to do with the angle of the forces through the welds?
As you may have gathered, I don’t know much about bike design, but I would really like to know what this is about! Cheers!