In ordinary composition, use orthodox spelling. Do not write nite for night, thru for through, pleez for please, unless you plan to introduce a complete system of simplified spelling and are prepared to take the consequences.

In the original edition of The Elements of Style there was a chapter on spelling. In it, the author had this to say:

The spelling of English words is not fixed and invariable, nor does it depend on any other authority than general agreement. At the present day there is practically unanimous agreement as to the spelling of most words.... At any given moment, however, a relatively small number of words may be spelled in more than one way. Gradually, as a rule, one of these forms comes to be generally preferred, and the less customary form comes to look obsolete and is discarded. From time to time new forms, mostly simplifications, are introduced by innovators, and either win their place or die of neglect.
The practical objection to unaccepted and oversimplified spellings is the disfavor with which they are received by the reader. They distract his attention and exhaust his patience. He reads the form though automatically, without thought of its needless complexity; he reads the abbreviation tho and mentally supplies the missing letters, at the cost of a fraction of his attention. The writer has defeated his own purpose.

The language manages somehow to keep pace with events. A word that has taken hold in our century is thru-way; it was born of necessity and is apparently here to stay. In combination with way, thru is more serviceable than through; it is a high-speed word for readers who are going sixty-five. Throughway would be too long to fit on a road sign, too slow to serve the speeding eye. It is conceivable that because of our thruways, through will eventually become thru — after many more thousands of miles of travel.

Thank you Strunk & White!

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