Kit and the Widow are a sophisticated and enduring cabaret act of much skill and polish, at least when not reading the words from a music stand.  Dillie Keane, founder and stalwart ofFascinating Aida has become the sort of national comedy institution round whom people should be taken in boats to marvel at her brilliance, and Noel Coward is arguably the country’s finest theatrical composer-lyricist of the 20th century, certainly our only one to bear comparison with Cole Porter or the Gershwins.

So why does the fusion of these elements work only sporadically in the revue format Cowardy Custard currently ending its tour in Richmond? It seems to be a question of ‘trying too hard’.  Coward’s lyrics were so carefully crafted and polished that even adjusting a syllable can unbalance the delicate perfection of his phrasing, and when the principals perform it with such overemphasis – Hesketh-Harvey ices all his words like wedding cake – it feels forced.

Comparing this production with the forty-year old original is possibly unfair – at theMermaid in 1972 the material was shared among a cast of twelve stretching from the sublime jazz singer Elaine Delmar to comedienne Una Stubbs whereas here five performers strain to produce variety in the staging, or enough light and shade in the singing.  Recalling the comic timing and gentle contralto of Patricia Routledge delivering ‘Marvellous Party’ was made more painful by watching Keane contort it into a pantomime drunk sketch, hammering each verse ever more bluntly into the eardrums of the front rows of the stalls whilst losing control of her limbs, clinging to the piano, and rolling her eyeballs like an electro-convulsive.

The audience lapped it up, though, and so did two mainstream critics – Charlie Spencer of the Telegraph made a pilgrimage to Lincoln and thought it “a classy delight” and Keane’s rubber-legged drunk act ‘hilarious’, although he felt as uncomfortable as we did at ‘London Pride’ being set to a background of Ken Livingstone commenting on the 2005 London bombings.  At Guildford, Mark Shenton of The Stage found the material “smart and revealing” and Keane “priceless” but overall he saw the show, like the custard of its title, as oversweetened and lumpy.

We’d mark it “not yet suitable for London” although the two young performers drafted in to dance and to sing the songs gauged too difficult for the cabaret comedians are excellent: Savannah Stevenson has a glorious voice and when not being too puppyish, Stuart Neal has a winning delivery in both the comic and straight numbers, ‘Matelot’ being his finest hour.

“Gallant old troupers, you’ve bored us all for years” cuts Coward in a satirical song about old theatrical stagers ‘Why Must The Show Go On’ … and delivers his own verdict.  To keep such glorious material fresh for the new audience, it needs newer voices.

Find another ten performers like Stevenson and Neal, and re-stage it.

Cowardy Custard continues at Richmond until June 4, tickets from Ambassador Theatre Group here