Actually, random search works a lot better than grid search for hyperparameter optimization. Usually, only a small number of hyperparameters actually matter, the trick is figuring out which ones. Grid search wastes time on irrelevant dimensions.
That said, any sort of hyperparameter optimization is extremely computationally intensive so random search is far from a panacea.
That said, any sort of hyperparameter optimization is extremely computationally intensive so random search is far from a panacea.