A dictionary of Proverbs (Oxford Paperback Reference)

diet see the best DOCTORS are Dr Diet, Dr Quiet, and Dr Merryman.
differ see TASTES differ.
DIFFERENT strokes for different folks
Of US origin: strokes = comforting gestures of approval or congratulation. Quickly picked up and used in a variety of parodic forms, as in a 1974 Volkswagen advertisement: Different Volks for different folks.

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  1973 Houston (Texas) Chronicle Magazine 14 Oct. 4 The popular saying around P [almer] D[rug] A[buse] P[rogram] is ‘different strokes for different folks’, and that’s the basis of the program. 1990 A. STODDARD Gift of Letter iii. Peter sends and receives letters. He dictates everything he writes. I send and receive handwritten letters. I write out everything. Different strokes for different folks. 2002 Washington Post 25 Feb. C2 There are many people who box for the sheer joy of it, there are even more who love to watch them do so; it’s not my own cuppa—though for many years it was—but what it says here is different strokes for different folks, so let the games begin. "tact; ways and means
  

The DIFFICULT is done at once; the impossible takes a little longer
A version of this is well known as the slogan of the US Armed Forces: the difficult we do immediately; the impossible takes a little longer. The ‘French Minister’ to whom this saying is attributed in quot. 1873 is Charles Alexandre de Calonne (1734-1802), appointed finance minister by Louis XVI in 1783: si c’est possible, c’est fait; impossible? cela se fera, if a thing is possible, consider it done; the impossible? that will be done (quoted in J. Michelet Histoire de la Revolution Frangaise (1847) I. ii. 8).

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  1873 TROLLOPE Phineas Redux II. xxix. What was it the French Minister said. If it is simply difficult it is done. If it is impossible, it shall be done. 1967 H. HARRISON Technicolor Time Machine iv. The impossible may take a while, but we do it, you know the routine. 1981 P. MCCUTCHAN Shard calls Tune iv. A well-worn precept of the British Navy was that the difficult was done at once; the impossible took a little longer. 1997 National Review 29 Sept. 66 That’s good, utilitarian, achievement-oriented American lingo. We do the difficult immediately, the impossible takes a little longer. ■ possibility and impossibility