It is generally wise to keep expectations low where secretary of states are concerned. The current incumbent, Chris Heaton-Harris, has done nothing to disprove the dictum.
In the last few days alone, Mr Heaton-Harris has managed to have a swipe at Taoiseach Leo Varadkar for voicing his entirely legitimate aspiration for Irish unity. He has praised the passing into law of the government's Troubles legacy legislation, a cynically conceived attempt to draw a line under the past which holds the distinction of being almost universally reviled and already subject to a slew of court challenges.
Mr Heaton-Harris also continues to insist that substantial progress is being made in talks with the DUP about restoring Stormont. This is dangerously close to taking the public for fools.
For his latest intervention he has returned to a favourite theme, namely public finances. In line with the Tories' austerity approach to funding – or, rather, defunding – public services, earlier this year Mr Heaton-Harris inflicted a what has been widely described as a punishment budget on Stormont. In the absence of locally elected ministers, the invidious responsibility for wrestling with departments' settlements and deciding what to cut has fallen on civil servants.
Now he has instructed them to launch public consultations on revenue-raising measures, including increasing rates for homes and businesses, bringing in charges for water and prescriptions and increasing university tuition fees.
Generating revenue this way is, he says, "not merely an option but a critical necessity".
It would be one thing to tighten the screw on Stormont's finances when a power-sharing executive, however dysfunctional, was in operation. It is quite another to do so when unelected officials are being left to carry the can, while the governance gap opened in the wake of the DUP's boycott widens to a chasm.
There is a school of thought that Mr Heaton-Harris reckons the DUP will be so appalled at the damage being inflicted on the north's public services that they are bound to have a Damascene conversion and return to Stormont.
If so, that is a mistake. Though it can be relied upon to almost always do the wrong thing, the DUP has repeatedly shown it cannot be shamed into doing the right thing.
Mr Heaton-Harris has a point when he says that Stormont's finances are a mess. That pre-dates the current crisis, and is the result of years of executive chaos and 13 years of Conservative government.
Fixing the problem requires proper long-term planning, not the secretary of state's shock-and-awe approach. The answer to our dysfunctional public finances cannot be yet more dysfunction.