ZeldaTheSwordsman wrote:"The size of Deluxe and Voyager figures have been consistent for many years now" -
that's my bloody point! 
They have consistently hovered in the 1/32 scale neighborhood (and those who aren't are in robot mode scale with those who are)! Which has meant that contemporary stuff like Prime Wars Deluxes are, in fact, comparable in stature and altmode size with older Generations and Universe stuff - I know, I've checked. So
why was it so unreasonable for me to expect Siege stuff to be the same size as Prime Wars stuff when as you say we've had consistency for years?
No matter their gains in mass, the Siege figures are ABSOLUTELY shrinking substantially in stature - what else do you want to call Siege Sideswipe only coming up to the bottom of Universe Sideswipe's armpit (or Titans Return Hot Rod's for that matter)? They're shrinking in altmode too, with Optimus and the Autobot Cars looking to be more in the 1/45 scale range.
As for going with AEC/movie stuff.. I know that obviously CHUG stuff contemporary or otherwise isn't
designed to do that per se, but the whole "hovering around 1/32 scale" thing has meant that plenty of figures essentially do anyway.
No, you're skipping over a significant portion of the past 14 years of the "Generations" line (starting in 2006 with "Classics"). The downsizing began roughly with the "Fall of Cybertron" line and continued into the Thrilling 30 line. It was at that point that we even saw a downsizing in the Leader class, as T30 Jetfire was a smaller, less massive, electronics-less Leader Class figure, compared to what we had been used to in the era of the Unicron Trilogy and the first couple of movie lines.
With the Prime Wars Trilogy, we got some more variance in size classes, but mostly because of gimmicks. Combiner Wars and Power of the Primes Deluxes and Voyagers are just a bit larger than normal due to structural concerns with the gestalt modes. They're lighter, so as not to add too much weight to the overall combined mode. Most of them have substantial cavities inside, to increase the surface area and structural support points while minimizing weight. In Titans Return, we've got another consideration in the form of having sizeable "cockpits" for the Titan Masters to sit inside the Deluxe and Voyager vehicle modes. Adding those cavities means that sometimes the robot mode will have a large area of nothing inside that all the other mass forms around. In some instances, though, Hasbro and Takara found clever ways to collapse those spaces to make more compact figures. That's why we get a considerably wide variance among size classes in Titans Return, but nothing is so egregiously out of scale compared to anything else that they don't look like they fit into the same line.
Those kinds of gimmicks are now gone with the Siege line, so we're back to where we were, essentially, with Thrilling 30 in terms of size and mass of figures overall. Just line within Titans Return, we really don't have a huge size variance among toys within the same size class from T30 onward. The difference between anything pre-Fall of Cybertron and post is, of course, going to be very noticeable, which is where the bulk of your comparison is being done, which is why you're setting yourself up for disappointment. Even pointing out oddities like the smallness of Classics Optimus Prime or the apparent tallness of TR Hot Rod, doesn't really help your argument. Classics Optimus is weirdly small compared to the rest of the Classics and Universe 2008 line up. TR Hot Rod does look tall, but it's because he's got high shoulders. Measure up to his head instead, and you'll find that he's not at all out of scale with his contemporaries. These are exceptions that prove the rule, so to speak.
ZeldaTheSwordsman wrote:As for why I think the CW Optimus/Motormaster mold prevents knee bend in gestalt mode unless you have the legs facing tires-side forward? I found out FROM EXPERIENCE that it does so. With the legs facing the intended way, several limbs will bump against the feet and have to be forced past to bend further. The Breakdown mold doesn't have any issues, but the Dead End/Streetwise mold does, especially the Streetwise version. Which makes it feel like the toy was designed more as a standalone Optimus, because you'd think -you'd hope - that if the mold was designed first as a combiner torso they'd have been paying better attention to clearances.
Well, from my experience, I've not had any trouble with bending the knees back 90 degrees on the Optimus/Motormaster mold. How are you getting "clearance issues?" Those wheels behind the legs don't bump into anything at the combination joint, nor on the back of any combiner limb. The robot mode feet of the Voyager torso stick off to the side. That's the intended configuration. Are you putting the feet at the back or front for some reason? That's not the correct configuration. Like I said before, I just earlier today played around with my Menasor after you made your complaints and found none of what you purported to be accurate. Why don't you take some pictures of what you think the problem is?
Wreck and Rule 
