No, I think that I've a pretty good idea about the variety of food in San Diego. Including references to "real" Mexican restaurants. I've absolutely no need to eat Mexican-style, but I'd rather like to try some whilst avoiding the problem of my wife's allergy. In the UK, Mexican food is equated with the "throw some more curry in, luv, I like 'em hot!" crowd and we are increasingly finding chillis added to everything, fairly blindly. I've no feel for the true range of the Mexican national cuisine, and am quite sure it is wider than it might appear from here.
Plus, I have read enough comments about Tex-Mex and similar to feel that much Mexican food on sale in the US just might be aimed at a similar indiscriminate clientele. The way the San Diego ads stress the real Mexican cuisine of certain restaurants does rather imply something about the rest of them - it may just be a matter of styles rather than substance but we'd prefer to be prepared.
Eating Mexican at home is not an option here. Unless we find something really nice whilst we're out there.