I seem to remember a woman saying it . I can remember some friends and I went through a stage of saying it (sad I know). She was blond and sort of ditsy.
Oh God that's going to annoy me now!
I remember it but can't think of the name. I remember the blonde woman and she used to say to her friend or sister " Oh it's phenonemal Sylv" as in Sylvia. Arrrgh I'll be racking my brains now!
It was a series called Sitting Pretty, the main character was Annie - who said "Phenomenal" in a strange sort of accent, who is broke after her husband dies leaving her with nothing . She has to go and live with her sister and family on a farm but she (Annie) still has airs & graces even though she's not as posh as she thinks she is.
It was a John Sullivan comedy - Only Fools etc it wasn't, but not that bad a series. I sort of felt a bit sorry for Annie