You are not serious, are you?
Oh, yes you are.
Come on.
Have you asked yourself why there are no TOCA, Enthusia, Shift or PGR with us anymore? Why Codemasters decided to listen to Gavin Raeburn in his insane idea to go more "casual" and earn millions in process if heritages of bot TOCA and CMR gets destroyed (did not happen)? Why did Konami decided in the last minute to cut the funding of Enthusia's 900-wheel project and drastically cut the marketing in half? Why did EA decided to stop the development of Shift after both games sold impressive 8M combined on all platforms? Why Microsoft insisted to launch all PGR games in the same time with their Halo games?
What is completely undeserved is how all publishers above decided to treat their franchises. Sales of GT games are all 100% deserved. Especially when you take into concern how they were blatantly underrated by reviews during launch times, especially be US media outlets.
Toca RAce Driver 3 for PSP was simply 1:1 port of PS2/XB/PC game. It has astonishing list of tracks and venues, same as the *big* game. But it was completely non-drivable in Simulation mode (even in other modes) and majority of higher-tier races were hell because of that (races with many laps and homicidal AI). With exception of on-paper content, TRD3 on PSP was not a good game from driving standpoint.
In the same time, GT PSP is perfect hadndheld driving game. It has great physics, totally made to fit portable device (although device itself is not ergonomic enough to justify proper riving, same as Vita IMO) and it has structure made perfect for portable game: self-assigned level of challenge with progress based on previous success, randomised structure of vehicle availability on order to cater "returning to game" procedure and stunning online options for a PSP game. I can accept how many fell short to accept GTPSP as it was, but IMO it is the best handheld racer ever from any point imaginable.
Polyphony did a lot of mistakes with GT in the past years and didnt got any damage for it in terms of sales, i agree that a good part of the fault was the publishers being idiots but come on, if any of those games had the sales they deserve they would be alive, PGR4 deserved lots more sales, its an amazing title, its was a better arcade game than GT5 was a simulator. It was a great game with little flaws.
For Enthusia you mention cutting the 900° wheel support like its a huge feature that make the game deserve to sell like crap, that game was very good and deserved to sell a lot more.
Toca 2006 for PSP was great too, making a 1:1 port for PSP was amazing considering that Polyphony wasnt able to do that with GT, argue whatever you want, GT PSP is a dissapointing cutdown/dumbed port, they removed some of the best elements of GT, i had way more fun with GT2 on my PSP than with GT PSP because i could race with more than 3 oponents, upgrade my cars and have a career mode. It bore me to dead after the driver challenges (or licenses test).
3 cars on track, no customization, no real career mode (as much as you try to spin into something good) made the worst Gran Turismo ever, like i said, the only bad game in the series and it hurt because i got PSP for that game and they spend years making it and kind of fooled us showing us mockups of the UMD at PSP annoucement.
As for GT5, i dont think the reviews were underrated, i got the game since day one and it was a very flawed and unpolished experience compared with usual high standards of Polyphony Digital, maybe you are thinking about what the game it is now, but when was release those review were deserved, PD did a good job working on the game to make it something much better than out of the box.
You make some good points about the publishers, i´ll give you that but i still think those games didnt got the sales they deserved and the last 3 GT games had more than derserved.
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About the videos: I love how the suspension looks, the R8 video is amazing.
My realistic request for GT6 is better audio, i think in a game that looks so good is unacceptable that still so weak in the sound department, they need to fix that because the rest of the track experience is years ahead of the sound department.
For the PS4 version i really think they need to take advantage of the trackpad of the DS4 to use it in a livery editor, it could be as unlimited as Forza vinyl editor but far easier to use and more intuitive, the whole manipulation of the layers with your fingers has too much potential to not use it.