The coach of the Redskins - whoever - in 1978, 1979, on into the 1980s can count on eyeballing across the field, two Dallas game days per autumn, the fellow who's always been there: Tom Landry.

Landry's previous 11-year contract as Cowboys' head coach since their NFL inception expired in 1975. He has worked 2 1/2 years without one. Until yesterday, when it was announced he has signed for five more years. No financial terms disclosed; "the only reason we signed one was because of the legalities involving taxes," said Landry - who has yet to exercise an option allowing him to purchase 5 per cent of the club.

"I've always felt that because of the friendship with Mr. Murchison [club owner Clint Murchison] and with Tex [president-GM Tex Schramm] it didn't really matter if I had a contract." He said he will continue coaching as long as it stays enjoyable and a challenge - "three of five years or whatever; it's an arbitrary figure. If I get tired of it I won't coach any more."

George Allen's hours of travail these past couple of days have been happy hours for Landry - who weathered an 18-46-4 ledger the first five years with the expansion Cowboys but is 120-40-2 since 1966. Sunday, the eighth straight win for Dallas' fastest getaway ever; Monday evening, guest at the wedding of Craig Morton, one of his former players, then - if he bothered to watch TV - the sight of the Skins losing; yesterday, the new contract; and now, an extra day to prepare for the other NFC East challenger, since Cowboys vs. Cards is the next Monday nighter.

Some 750 attended the marriage of Denver QB Morton and Dallas model Susie Sirmen in candlelight ceremonies at First Presbyterian Church in downtown Big D. The newlyweds left church in a carriage pulled by giant Clydesdales - do we sniff a beer commerical? . . .