How does your Club treat eligibility for 2's

Apparently so. Has happened to me in a singles and pairs event, both times with competitive scores. Handicap secretary DQ'd for not signing into PSO prior to start time. Whether it's right or not it's enforced robustly
Ah yes... you didn't sign into the Comp prior to going out.... DQ.
I thought you'd meant failing to enter score to PSI
 
I don't think you can DQ for this.

That is correct a club cannot DQ for failure to enter a score on the PSI computer

3.3b(2)/1 – Players Are Required to Enter Only Scores on a Scorecard
There is a difference between requiring players to enter a score for a round into a computer (such as for handicapping purposes) and being required to enter hole scores using an electronic form of scorecard approved by the Committee (such as a mobile scoring application).

The Committee may require players to use a scorecard other than a paper scorecard (such as an electronic form of scorecard), but the Committee has no authority to impose a penalty under Rule 3.3b(2) for failing to enter scores elsewhere.
 
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