Peter Robinson's absence adds to the general sense of gloom around Welfare Reform and the future of Stormont.
Like him or loathe him, most rivals concede that Mr Robinson, along with John Hume, is the most able political strategist of his generation.
He was largely responsible for cobbling together the Stormont House Agreement which wrung low interest loans out of the Tories in return for Welfare Reform. It also set up a top-up scheme to ameliorate the worst of the cuts.
That is really the only solution on offer and officials were very keen that he should remain as leader of the DUP until a deal was made.
"Peter is a dealmaker, we need him," one very senior British source told me in January.
He was under intense pressure. The failure to strike a budget threatened all his achievements and even devolution itself. Relations with Sinn Fein have hit rock bottom. He has, on occasion, disappointed them because of the need to maintain unity in his own party and appease the right wing traditionalists.
The DUP now has an identifiable liberal faction and one which favours the religious right. The centre of the religious right - the "tea party DUP" - is Lisburn, where Paul Givan, Jonathan Craig and Edwin Poots are based. It also includes the likes of Jim Wells, Jonny Bell and some MPs.
He also has long-term pressure resulting from his wife Iris' condition. She had a breakdown in 2008-9 and an affair with a younger man.
Although she is said to be much better, she is still not entirely back to full health, according to friends.
A final pressure may be the rumours of Mr Robinson's resignation, which have been going for over a year.