I had played the DDG for a few years before I started to analyse it. First I just recorded a couple of interesting games of mine, and tried to invent better moves afterwards. I have never dreamt of complete analysis, but only finding yet another move to keep White's initiative. Especially I am more motivated now, having seen that the DDG is officially busted in several books. It cannot be that easy.
Seriously, the DDG pages are far from being serious chess analysis. I have only divided games under similar opening variations, and tried to identify common ideas behind the main lines. The worst thing is that there are so few DDG games around, so most "ideas" are my own, and thus not very reliable. I have always liked tactics more than positional play, so I tend to look for attacking possibilities, ignoring strategical viewpoints. But, on the other hand, being a sharp gambit, the DDG is mainly tactical in nature.
It would be stupid to try to give exhaustive analysis on the DDG, so I only try to find ways to keep White's game active, to keep the initiative, put pressure upon Black, provoke Black to make an error -- or even a slightly incautious move. After all, more games are won by attacking than defending. The best that White can hope is to play against Black who just waits passive, tries to build a solid position, looks for small weaknesses that could be used to gain endgame advantage.
It is very encouraging to remember that only 5 % of the chess players are masters. Yet most opening books are written for them. I would not recommend the DDG to masters for non-blitz games (on the other hand, who am I to recommend anything), but for blitz the DDG is just perfect. I have a few master scalps even though I am well below the master level.
There are many unbelievers who claim that the DDG is too unsound for serious tournament play. But they forget that thrill of playing a strange gambit -- which keeps the Grob Attack and the BDG still alive and kicking hard. It should also be remembered that the Evans Gambit was analysed to death in the 1970's... There are very few absolute truths in chess.
Above all, the DDG is fun to play, and it is better in practice. Even an NPCA (Non-Professional Chess Association) World Champion might play it.