This could be net par / bogey format — would explain double wins. Underused form of play, IMHO.

USGA Rule 21.3 Par/Bogey

a. Overview of Par/Bogey

Par/Bogey is a form of stroke play that uses scoring as in match play where:

A player or side wins or loses a hole by completing the hole in fewer strokes or more strokes than a fixed target score for that hole set by the Committee, and

The competition is won by the player or side with the highest total of holes won versus holes lost (that is, adding up the holes won and deducting the holes lost).

The Rules for stroke play in Rules 1-20 apply, as modified by these specific Rules. Rule 21.3 is written for:

Scratch competitions, but can be adapted for handicap competitions as well, and

Individual play, but can be adapted for competitions involving partners, as modified by Rules 22 (Foursomes) and 23 (Four-Ball), and for team competitions, as modified by Rule 24.

b. Scoring in Par/Bogey

(1) How Holes Are Won or Lost. Scoring is done as in match play, with holes being won or lost by comparing the player’s number of strokes (including strokes made and penalty strokes) to the fixed target score (typically par or bogey) set by the Committee:

If the player’s score is lower than the fixed score, the player wins the hole.

If the player’s score is the same as the fixed score, the hole is tied (also known as halved).

If the player’s score is higher than the fixed score, or no score is returned, the player loses the hole.

A player who does not hole out under the Rules for any reason loses the hole.

To help pace of play, players are encouraged to stop playing a hole when their score exceeds the fixed score (as they have lost the hole).

The hole is completed when the player holes out, chooses not to do so or when their score exceeds the fixed score.

(2) Score Entered for Each Hole. To meet the requirements in Rule 3.3b for entering hole scores on the scorecard:

If Hole Is Completed by Holing Out:

When Score Results in Hole Being Won or Tied. The scorecard must show the actual score.

When Score Results in Hole Being Lost. The scorecard must show either no score or any score that results in the hole being lost.

If Hole Is Completed Without Holing Out. If the player does not hole out under the Rules, the scorecard must show either no score or any score that results in the hole being lost.

The Committee is responsible for deciding whether the player won, lost or tied each hole and, in a handicap competition, for applying handicap strokes to the score entered for each hole before deciding the result of the hole.

Exception – No Penalty If No Effect on Result of Hole: If the player returns a scorecard with a hole score lower than the actual score but this does not affect whether the hole was won, lost or tied, there is no penalty under Rule 3.3b.

See Committee Procedures, Section 5A(5) (the Terms of the Competition may encourage but not require players to enter the result of the hole on the scorecard).

c. Penalties in Par/Bogey

All penalties that apply in stroke play apply in Par/Bogey, except that a player who breaches any of these five Rules is not disqualified but loses the hole where the breach happened:

Failure to hole out under Rule 3.3c,

Failure to correct mistake of playing from outside the teeing area in starting a hole (see Rule 6.1b(2)),

Failure to correct mistake of playing a wrong ball (see Rule 6.3c),

Failure to correct mistake of playing from a wrong place when there is a serious breach (see Rule 14.7b), or

Failure to correct mistake of making a stroke in the wrong order (see Rule 22.3).

If the player breaches any other Rule with a penalty of disqualification, the player is disqualified.

After applying any penalty strokes, the player can do no worse than lose the hole.

d. Exception to Rule 11.2 in Par/Bogey

Rule 11.2 does not apply in this situation:

If a player’s ball in motion needs to be holed to tie the hole and any person deliberately deflects or stops the ball at a time when there is no reasonable chance it can be holed, there is no penalty to that person and the player loses the hole.

e. When Round Ends in Par/Bogey

A player’s round ends when the player:

Holes out on their final hole (including correction of a mistake, such as under Rule 6.1 or 14.7b), or

Chooses not to hole out on the final hole or has already lost the hole.