Given the fact that DP6 now supports Cocoa plugins means they have changed quite a bit. However, the fact remains that in pure coding issues, Cocoa is NOT as efficient as Carbon. Objective-C has overhead associated with how it's message system works, and because of that, there can be *some* performance hits depending on how things are coded. Is this a big deal? No, as plenty of Cocoa applications SCREAM (and it's easier to code in) but let's be clear, Carbon is not causing slow down.
Will 64-bit require a complete rewrite? No. But it will take a lot of work going through and making it selectable between say 32-bit and 64-bit because I cannot imagine them make it fixed to one value for performance reasons alone. Not only that, if you've already finished a song in 32-bit, you might want to keep it there as you've already *mixed* with regard to any affect of using 32-bit to begin with.
I am not saying that DP doesn't need to be a bit more efficient, and it is clear Motu is trying to find ways to do this, but saying it needs to be rewritten is an absolute waste of time. Seriously. DP is based around a specific *environment* that people use and love. To change the basics of DP for speed purposes could and more likely will change the features that DP has. The reason DP works at the speed it does is more likely the freedom DP has in how it has been made. Compared to the likes of Logic, there are a LOT of things in DP that work better but clearly at the expense of speed.
Instead, I'd rather see Motu take the code they already have and figure out how to make it faster. Which, is what they are doing. Taking away features is just going to piss people off and that's what would happen with a complete rewrite because the architecture would be different more than likely and not behave exactly the same. I mean really, DP is VERY complex internally in terms of real time processing.
I look forward to see how DP6 works.

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