I think eric and Scawen do the work of 20 people, because rework 75% of the physics engine, putting more contained for s3,+ colossal challenge of the new tires system (too difficult for Scawen alone, that's why it's stuck).
It is quite normal that the development stagnates, I think developers are overestimated their ability to do all that, and it is quite normal that it takes more than 4 years, what a team of 20 can ends all this in 6 months.
If there is something going wrong, I think they may very well call the community for help.
and sorry for my bad english
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