I sorta agree with both sides of the "let's just talk this out until everyone is on the same page" thing. Evidence suggests that unless you are metalurgist level you can't really "understand" these issues. Even at that level there are areas of practice that can bend the rules quite successfully. "There are more things in heaven and earth... Than are dreamt of in your philosophy".

I think the Tigability thing is largely just marketing, since when did making stuff really hard for higher strength become a huge objective in these kinds of structure? 100 years of practice is all in the opposite direction. What it really shows (as far as I can tell) is that even when you go in the opposite direction of sense, the process is well strong enough to deal with it, given the parameters of these joints. That has always been the case, but due to the huge investment in lug theory this industry just keeps digging hoping to reconcile two contradictory points that often crop up in the same product line, or product. 853 is mostly superior due to the higher strength of the tube outside the weld zone, which allows lighter structures to be built, when well designed, however joined.

If one really wants to get into it one would have to look at the structure in the casting like weld face/reenforcement, in the fusion zone where the base metal and filler mixed, in adjacent base metal that was super heated, in adjacent metal that was not heated above the trans temp... Just for starters.