I agree that DTA can be more of a hindrance in the hands of someone inexperienced in the art of determining proper indexing. It will (many times) suggest indexes where the first column has super low cardinality which causes a huge number of reads on INSERTs especially when the Insert causes the index to split to "make room" to the point where timeouts are actually caused.

I can't speak much about the Debugger but it's been my experience with other Debugger's that it's no substitute for some good ol' horse-sense-due-to-experience. In fact, I see them as sometimes being detrimental because people will sometimes use them as a crutch instead of learning from them.

I agree that having tools are good and every DBA should strive to learn as much about them as they can... if, for nothing else, to learn of the caveates they have and the damage they can cause when used incorrectly.