That's consistent with the idea that an action taken to serve ones interest doesn't become virtuous simply because it's incidentally the right thing to do. Anyone who wants to gain respect with a public pledge rather than simply rally those who agree with their predetermined decisions should make a pledge that will actually cost them something (rather than a pledge that costs them nothing personally but costs the nation any chance of policy reform.) How I feel about the terms of the pledge itself is neither here nor there to that; a pledge to only appoint pro-choice judges is just as bad, and a good example of how Democrats in the '70s and '80s let themselves become so captive to radicals in the base that Republicans could routinely and successfully paint them as too extreme for the general electorate. Pledges and promises CAN mean a great deal, but a pledge to pre-existing goals is just a rallying cry to pre-existing supporters and categorical dismissal of opponents, not a visionary statement of principle.