The phrase to play a good knife and fork means to eat heartily.

This phrase occurs, for example, in the column An upward glance, by Tim Cummings, published in the Ravalli Republic (Hamilton, Montana, USA) of Friday 14^th December 1984:

A while back I was heartily breakfasting with a friend of mine.
The food was prepared for us in mammoth quantities. A giant, steaming bowl of scrambled eggs sat before us, with bisquits, toast, hash browns and a plate of sausage.
We played a good knife and fork at this banquet.

The earliest occurrences of the phrase to play a good knife and fork that I have found are as follows, in chronological order:

1-: From Augusta Triumphans: Or, The Way to make London the most flourishing City in the Universe (London: Printed for J. Roberts, 1728), by the English novelist and journalist Daniel Defoe (1660-1731):

All Housekeepers might be excus’d, if a Tax of only 1s. per Annum were levied on every Batchelor within the Bills of Mortality, and above the Age of One and Twenty, who is not a Housekeeper; for these young Sparks are a Kind of unprofitable Gentry to the State; they claim publick Safety and Advantages, and yet pay nothing to the Publick, nay indeed, they, in a Manner, live upon the Publick, for (on a Sunday especially) at least a Million of these Gentlemen quarter themselves upon the married Men, and rob many Families of part of a Week’s Provision, more particularly when they play a good Knife and Fork, and are of the Family of the Tuckers.

2-: From A New Plain and Useful Introduction to the Italian. Compiled from the best Grammarians, who have wrote in the Tuscan Language. Together with a Choice Collection of Italian Idioms. Collected from the most noted Authors, with the proper English adapted: For the Benefit of such as are desirous to have a thorough Knowledge of, and Speak correctly, this useful and beautiful Tongue (London: Printed for J. Wilcox, 1739), by John Kelly (1680?-1751):

A tavola non s’invecchia. * We say, he’s a good trencher man, he plays a good knife and fork; the time he is at table, he never grudges, or thinks long.

* The Italian proverb A tavola non s’invecchia translates as At the table one does not get old.

3-: From The Memoirs and Adventures of the Marquis de Bretagne, and Duc d’Harcourt. Written originally in French; and now done into English, by Mr. Erskine (Dublin: Printed by Oli. Nelson, 1741)—translated from Mémoires et aventures d’un homme de qualité, qui s’est retiré du monde, by the French novelist Antoine-François Prévost d’Exiles (1696-1763), known as Abbé Prévost:

He was not rich, the principal Part of his Revenue consisted in the Presents from some Lords, and particularly the Duke of Montague, who gave him a Pension of near two hundred Guineas. He was not liable to any great Expence, being very welcome when ever he pleased, to the best Tables in England, where I have been told he played an exceeding good Knife and Fork.

4-: From A New English Grammar, Or, Guide to the English Tongue (London: Printed for R. Manby and H. S. Cox, 1746), by John Kirkby:

A Metonymy (Putting one Name for another) is the Change of a Word from its proper Signification to another which has some Relation to the former. And this is of seven Sorts, viz. […] (4) Of the Adjunct for the Subject; as He is a good (Player upon the) Fiddle : He handles a good Knife and Fork, i.e. He eats heartily.

The phrase to play a good knife and fork gave rise to the nouns knife-and-fork man and knife-and-forker, which designate one who plays a good knife and fork, a hearty eater.

The noun knife-and-fork man occurs, for example, in Grievance XXVIII.—Ordinary Frequenters of Ordinaries, published in The Sporting Magazine or Monthly Calendar, of the Transactions of the Turf, the Chase, and every other Diversion interesting to the Man of Pleasure, Enterprize & Spirit (London, England) of April 1812:

At public dinners, or tables d’hote, you are always sure to meet a number of gormandisers, who set all good manners at defiance, struggling to help themselves to the choicest bits, even if ladies are present. The enormous appetites, likewise, of these scramblers—these dexterous knife-and-fork men, will sometimes preclude you from enjoying a comfortable meal off a particularly favourite dish—say a roast leg of lamb, or a boiled turkey.

And the noun knife-and-forker occurs, for example, in Literary and Literal, published in The Comic Annual (London: Hurst, Chance, and Co., 1830), by the British poet and humorist Thomas Hood (1799-1845):

The founder of Hog’s Norton Athenæum
Fram’d her society
With some variety
From Mr. Roscoe’s Liverpool museum;
Not a mere pic-nic, for the mind’s repast,
But tempting to the solid knife-and-forker,
It held its sessions in the house that last
Had killed a porker.