Bob Dylan made a stop on his Never Ending Tour in Cardiff's Motorpoint Arenalast Thursday. Even though the tour name hasn't changed since 1988 this current leg is in support of his latest release, his love letter to the classic American songsof his youth,Shadows in the Dark.

The Arena was packed with fans of all ages. But, whether they were millenials or over-the-hills, anyone caught trying to take a snap of their icon or even a selfie with their iPhone was hunted down by the flashlight-wielding wardens, who paradedlike so many harassed teachers trying to police a class of cunningly choreographed school children.

As soon as one naughty boy or girl brokeranks tofire off theirflash a warden would race toward them brandishing their torch so as to ruin any chance of a good photo. At the same time anywhere between 20 and 200 other fans would start snapping while the warden's back was turned. A brilliant ploy and I'm sure all 5,000 strictly seated ticket holdersgot a chance to take a pic by the end.

And perhaps that should be enough: taking a photo of a living legend. Just seeing the man who wrote Like a Rolling Stone, Mr. Tambourine Man, The Times They Are a Changin' andMake You Feel My Love should be enough, shouldn't it? As long as you don't honestly expect him to sing any of those songs on stage.

And why should we?

Apart fromMake You Feel My Love,made far more famous by Adele's 2008 cover of it, all those hitswere written by 1965, before young Bobwas even 25 years old. Dylan, now 74,wantshis modern Music to be loved by his modern fans - fans like me, who know the60s and 70s material is classic but love his retro-activereturn to roots.My step-father is of the old guard.

He loves the brilliant new material but is tiedin time to the Best of Bob days.

So when Dylan finally launches into anencoreofBlowin' in the Wind we should allcelebrate - unless ittakes two verses to work out which songhe's singing. The problem isn't that he can't sing any more.The problem is that you can't hear what he's singing.

The great poet of popular music has bad diction.

The odd thing is that although he treats his own material with such disregard, he is close to reverential in his interpretations of the Great American Songbookrepertoire from his latest album. The band, whose post-rockabilly grooves play fast and loose withthe Dylan originals, are a tight, concise jazz quintet when backing crooner Bob through classics likeAutumn LeavesandWhat'll I Do?Suddenly we recognise the melodies, even to the songs we've never heard before. The lyrics are intelligible and Dylan holds out notes with control and finesse. If only one of the greatest lyricists of our time couldtreat his own words with such care.

So who leaves a 21st century Bob Dylan concert happy? Insert your own punchline here.