I've had similar findings when I've played around with it. Although I'd caution riding with the saddle at the extreme range of their rails whether forward or aft. On my saddles when I've tried that a decent bump has sometimes felt like the rails may have flexed enough for the saddle to bottom out on the post of something. So I worry that that might increase my chance of the rails breaking.

Also, I carry more weight on my arms when doing this. On short rides, not an issue. On long rides I'm finding that if I only have a slight bend in my elbow that I'll eventually get some minor annoying numbness in my hands. If I work hard to keep a large bend in my elbows, then I don't have that numbness despite not having changed anything else but the angle in my elbow and I suppose any angle that might make to my overall body position.

My natural tendency in the past was to ride on way oversized bikes that kept my arms stretched out. I've shortened my stem and narrowed my bars on a bike that is arguably the smaller of the two suggested frame sizes for my 5' 11" height. And since keeping a large bend in my elbows still isn't quite comfortable or natural in itself for me, I'm wondering if I just need to keep at it or would the next smaller frame size bike have been a better bet for me.

One question I have for you is whether you consider yourself to ride near your max sustained output for your rides or do you keep quite a bit of reserve and ride at lower power output. I tend to also ride at higher sustained output levels and suspect that many that do will favor being more forward in relation to the BB than others that ride at lower power output than they are capable of.