Yes, MP Trailbreaker is lanky, but that's because he was lanky in the G1 cartoon. Typical with other Season 1 Transformers, Trailbreaker's design looks more like an athletic human than the actual toy. This is likely due to Floro Dery's design being reinterpreted (i.e. simplified) from Kohara Shohei's more detailed mecha anime designs. We had the same thing with other MPs like Sideswipe, Sunstreaker, Wheeljack etc. - all are lankier than their actual G1 toys. You can also compare and contrast the designs of the Season 1 TFs with Season 2, as the S2 designs were created exclusively by Dery based off the toys, and are thus relatively more toy-accurate than the Season 1 designs. This is why Hoist isn't lanky like Trailbreaker, Red Alert has a broad chest with wheels on the shoulders, Smokescreen is stockier than Bluestreak and Prowl, the Coneheads have more toy-accurate body proportions with tiny upper legs and massive knees etc.
MP Trailbreaker is so ridiculously cartoon-like that they even gave him asymmetrical knees! At first it may look like the toy has been misassembled with two of the same side knees, but upon closer inspection you can see that it's not, because the screws are facing inwards; it's impossible to switch them around. They've been designed like this on purpose, and it is to match the cartoon design! That's a crazy level of attention to detail that we've come to expect from MP.
It will be interesting to see how much they've pre-tooled this mould as MP Hoist. I suspect that it will still be mostly Trailbreaker in proportions, but with things like the head and knees being tooled to look more like Hoist. I would be surprised if it were more extensively tooled to look more toy-accurate. I mean, MP Cordon and Spin-Out have new heads and shins to look more toy-accurate, but otherwise their bodies share MP Sunstreaker's Floro Dery Sunbow design proportions. I suspect that this will also be the case for Hoist; and if they choose to go down the path, MP Breaker and Lift-Ticket.
Reply With Quote
No other Optimus Prime toy, including the first two MP Convoys, ever bothered with this - let's face it - insignificant detail. But post-2016 MPs do! 
I tried using the instructions but hit a brick wall with the shoulders and ended up watching some Japanese video reviews; and this was challenging for me as someone who can read/speak Japanese... it must be even harder for those who can't read the instructions. But yeah, thankfully there are more non-Japanese videos out now, and I like EmGo's JTI videos which are usually devoid of any language and just let the visuals speak a thousand words. 
