The new Groboto fusion stuff looks very cool! That would be a major step forward for incorporating booleans into sub-d modeling work while before they were like oil and water.

From what I can see it has to be changing the topology of the existing sub-d objects on the fly and it is fairly easy for any automatic retopology method to introduce kind of stretched or squashed areas in the result, so it will be interesting to see if there tends to be any shape perturbations in the result, and it's also a big question whether any input mesh can be used or whether there are restrictions on the input topologies.

One of the strengths of NURBS modeling is not just that you can do booleans but also that you can form large parts of your model from 2D curves. It's actually the 2D curve focus that tends to make NURBS modeling easier for novices to get started with, and it's also where advanced users gain a lot of modeling speed from as well. The new Groboto Modo plug-in does not really bring that particular same aspect to the table, but it looks like it should be really useful for already experienced sub-d modelers to be able to merge forms together a lot easier than they could previously.

One thing that might be kind of weird is to only be able to apply fillets as the result of doing a boolean, it's not unusual for something that you want to fillet to be an edge of the natural outline of a shape for example rather than only something coming from a boolean.

It will be cool to see more demos of it, it's certainly going to be a lot more useful to people than the stand-alone Groboto was.

- Michael