It is not unusual for developers to create rough prototypes of their games before going into full production, but these tend to run in the same engine just with rough textures and physics. (caiminds.com)
The unit I got to hear was an incredibly rough prototype, and they told me it would be at least two years before they had something consumer viable. (windowscentral.com)
He also helps run 1GAM Dublin, a gamedev meetup where you are encouraged to share rough prototypes, which has been held monthly since April 2013. (imirt.ie)