Add Row button adds three rows (not one)

In Dropbox - UCCJEA - Intake Form (04).pdf there are two tables. Both tables have a single "Add Row" button. In the top table, clicking it once actually adds three rows (not one, as it should). In the second table, it operates as it should (adding only one row). However, for the life of me, I can't fathom why.

The top table uses this code:

form1.#subform[0].SUB_of_Table1.Table1.HeaderRow.Subform3.AddButton::click - (JavaScript, client)

Table1._Row1.addInstance(true);

The bottom table uses this code:

form1.#subform[0].SUB_of_Table2.Table2.HeaderRow.Subform2.AddButton::click - (JavaScript, client)

Table2._Row1.addInstance(true);

Barring some form of document corruption, I cannot begin to guess why the top adds three rows, but the bottom only one. This is driving me crazy.