I appreciate that. Neither was I. I think its the way it was written (or read) that seemed dismissive, as if I couldn't know that unless I used serious deductions. I often do serious deductions, just privately.
Anyway, I personally think the underscale is noticeable, all the moreso with the new Jabba. 1/2 inch is the differnce between someone being 6 feet and 5' 6 inches. In life, what height would you rather be? So it matters in 1/6th. Look at all the madness we've all gone through to get Vader down to the 13.25 inches he's supposed to be.
Anyway... I think you and I agree -- its sometimes hard to tell -- but put simply: that the old Jabba is smaller than the new Jabba.
It most certainly is underscale - and I've never argued the reverse. It's solely about how noticeable it is next to correctly scaled figures (ie not next to the new Jabba,) and all I'm saying it's not all that noticeable, and that a simple tweak fixes most of it.
That (I think) is where we disagree.
The point I was making about the old Jabba thread (that I went through recently because so many people were building palace dios back then) is that while there are people mentioning that Jabba as undersized, it's literally a couple of people, and the one who started it was arguing the Illusive Jabba was correct 1/6 size - so should be immediately discounted for idiocy (not coincidentally, he owned said Illusive statue.)
What you don't see in that thread is - in an era when standard SSC 1/6 figures were larger overall by today's standards (20% larger "bobble" heads and hands than today's figs for example ) is a load of people speaking as if they had just received a Medicom Vader that they were trying to display with regular 1/6 figures - "ugh, this Jabba looks too underscale/short." And many of those people are still active on here - people who would know immediately if it was clearly underscale. Which suggests to me that while the old Jabba is most definitely a bit underscale, it's not by anything really obvious with figs around it to a majority of collectors.
And the examples of say 14" Vader etc being too tall and the 1/2" making a big difference - it's not really comparable to this. Using your example, you stand next to someone who's 6" taller and you know it, but the difference between a male and female rhino in front of you at the zoo, both massive (one is 90% the size of the other,) isn't much, even if one is a little taller than the other if you take out a measuring tape.
The core point I've been making (and yes, I am keeping my old Jabba for my palace dio display so I have a dog in this fight as Mel Gibson would say) - is that while it's undersized, it is not by much in comparison to other figures, and the vertical 1/2" shortfall can be mostly made up by placing a 3/8" riser under him which isn't noticeable (I already did it, and it's fine.)