THIS ALBUM has given Rod Stewart his highest entry (No 4) in the American charts for years - so it must be good, right? Well, no. Yet, in the world of the record business, where celebrity and commercial imperatives don't merely obscure questions of artistic merit, they supersede them, It Had to Be You is counted a success. You can picture the meeting: a once unimpeachable interpretative singer comes back from a brush with cancer and makes a dud album (last year's Human); where next for Rod the Mod? Why, team him up with the classics of the American songbook; it can't fail. But it does, woefully. Stewart sleepwalks through standards such as Every Time We Say Goodbye and These Foolish Things, his cod-American vowel