For the majority of games a genuine physics engine is unnecessary, as good results can be achieved with lots of simple equations and 'if' statements.
I'm not saying
everything is possible, but results can be very convincing, and probably run quicker than a complex engine running in addition to (or indeed as part of a new DB version) your code.
I may be wrong, but I personally have never come up against a problem and have programmed almost every type of game with DB1 (fps, rts, racing, 3d platform, rpg, survival horror/adventure, rythmn action, a GTA3/Crazy Taxi clone, even a 3d Fighting game!).
Once I have translated the projects into DBPro code I am thinking of releasing the demos and source code as a resource for other people, and also to see if anyone can further optimise them, or suggest improvements
* If the apocalypse comes, email me
*