Sure, but success has to have something to do with it. Guinsoo gave dota to icefrog like 6 years ago and if you compared that game to now you could argue that it is a completely different game. The years Icefrog has presided over dota have also been by far the most successful (in terms of new players and competitive scene).
You have to sympathize with Valve here. They are creating a game called DOTA 2 (they explained why they are calling it that) and if you are going to sink your company's time and money into something like this, you need to be able to control the name.