The Bullets found out the hard way last night why New Jersey net guard John Williamson is called "Super."

Williamson could have worn a big "S" on the front of his uniform and no one would have laughed after he destroyed Washington with 40 points in the Net's surprisingly easy 108-100 triumph at Capital Centre.

It was only the second loss in 13 games for Washington, both at home. The Bullets have struggled so much lately in the Centre that Coach Dick Motta wishfully said last night: "I'd like to play more games on the road. At least we concentrate more."

His club would have needed more than concentration to handle Williamson. who shook off Bullet guards and powered his way to a 15-for-23 shooting effort. He had 25 points in the first half, 1 in the second period when the Nets grabbed a 60-46 lead they never came close to relinquishing.

After being blown out against Washington weeks ago by 49 points on its home court, New Jersey chose not to run with their deeper opponent this time. And the Bullets played into the Nets' hands by turning in their worst all-around performance since the opening weeks of the season.

They did not shoot well, did not handle the ball crisply (18 turnovers) and were inept from the foul line (24 of 46). It was a team-wide case of the blahs and New Jersey benefited.

By outrebounding Washington, 46-36, the Nets cut off most Bullet fastbreak opportunities. And they shot 50 percent to quell ideas of a rally by the home team.

The victory was even more remarkable considering the Nets were finishing a six-game, 15-day road swing that included stops on the West coast. They won at Los Angeles and Golden State.

"They could hve let this one go and used the trip as an excuse," said Coach Kevin Loughery. "But they didn't. We knew we had to control the tempo. We didn't want to run with them. They've been incredible in the first half lately and we didn't want them to jump off to a big lead. They didn't. Things went like we wanted."

The Nets dominated the first period. They ran off the last 10 points of the period and the Bullets missed eight straight shots. The Nets added the initial two baskets of the second for a 28-18 lead.

Forward Bernard King had six of those points and, as in a form of basketball tag-team match, Williamson took over from his scoring twin the rest of the half.

Loughery was especially pleased that the Bullets, as usual, went to the bench at the start of the quarter. That put Charles Johnson on Williamson and the Nets immediately took advantage of the four-inch height advantage enjoyed by the New Jersey guard.

He scored seven quick points early in the quarter and five near the end. Another guard, Ed Jordan, had six points as the New Jersey backcourt accounted for all but five of its 36 in that quarter.

It was more of the same in the third, this time with Eric Money aiding Williamson. Money, who had four points at the half, wound up with 20 by making seven of 12 attempts after intermission.

But it was Williamson who was controlling the game. The Nets went to a one-four offense that had Williamson looking for his shot or passing off from the top of the key with his teammates set up along the baseline.

The result was a walk-it-up-the-court tempo and six assists from Williamson, who began the trip on the sidelines with thigh bruise.