Fergus O'Dowd is not a natural rebel. During his brief spell as a junior minister, Fine Gael regularly sent him on radio and television to defend whatever screw-up was dominating that day's headlines.
So when the combative Louth TD launches a stinging attack on Irish Water, it can only mean one thing - even government loyalists are no longer prepared to toe the line on an issue that has generated huge public anger and could ultimately cost many of them their seats.
O'Dowd's assessment of Irish Water makes Roy Keane's feelings for Alex Ferguson look positively warm.
He berates it as a "cosseted quango with a bonus culture" that has "abjectly failed" to communicate properly with its new customers.
By adopting such an "arrogant and uncaring" attitude, "almost as if there was a conspiracy to make it as bureaucratic and nonsensical as possible", the whole project has turned into "an unmitigated disaster".
O'Dowd (right) was effectively sacked in last July's reshuffle, even though some pundits had tipped him for a seat at the cabinet table.
He now looks like a politician whose best days are behind him, which makes his outburst easy to dismiss as a bad dose of sour grapes.
Since he was also the minister who drew up legislation to create Irish Water and steered it through the Dail, however, his criticisms deserve to be taken deadly seriously.
What he is describing sounds scarily like the HSE, a political project with the best of intentions that turned into a Frankenstein's monster nobody could control.
In fact, Irish Water's response to one of O'Dowd's main arguments has proved his point perfectly.
Even though one third of its staff are due to receive payments amounting to 14pc or 15pc of their salaries this year, we are assured that these are in no way "bonuses".
Instead, we should think of them as "performance related awards" - presumably like the awards in some areas of the Civil Service that go to every worker who has managed to avoid burning down the building.
Here is a classic example of the arrogance that O'Dowd has belatedly pointed out.
From the outset, Irish Water has had a nasty habit of talking to consumers as if they were either dishonest or clinically brain-dead.
It started with those glossy television ads that suggested they were really doing us a huge favour, continued when they spent a staggering €50 million on consultancy fees and has now resulted in the high-handed demand for PPS numbers that has annoyed many.
Enda Kenny's feeble response to O'Dowd is that everybody must understand why Irish Water was set up in the first place.
Frankly, with the meters already running and bills due in January, it is a bit late to start lecturing us now.
The reality is Kenny's government has badly taken its eye off the ball .
In the two Dail by-elections scheduled for Friday, campaigners report that water charges are being raised more often than all the other issues.
In next Tuesday's budget, Michael Noonan will outline in detail how he is using them to balance his books.
For the opposition, this is a stick they can use to beat the Government until well into 2015.
Ironically, it was Leo Varadkar who highlighted the basic political problem with water charges.
As the Health Minister recently pointed out, giving people an extra fiver in their weekly pay packets will not exactly cause them to weep with gratitude. Giving them a regular bill for hundreds of euro, however, will provoke a very different response.
Kenny's standard defence is that water charges are only being brought in because Fianna Fail wrecked our economy and the Troika put a gun to our heads. However, it was this government that gave birth to Irish Water and must take responsibility for its behaviour - which has infuriated even those who accept the principle of paying for water.
While O'Dowd has refused to personalise his attack, it would appear he is targeting two people in particular.
One is ex-Environment Minister Phil Hogan, now an EU commissioner, who can regard the controversy as water off a duck's back. The other is Enda Kenny - a Taoiseach who has made plenty of enemies in Fine Gael over the last fortnight alone and can ill afford any more.
There are quite a few things that Kenny might try to defuse the water charges time bomb. He could follow O'Dowd's advice and make sure that Irish Water's bonus culture is "strangled at birth".
He could put a consumer advocate on the board to see that customers are not completely fleeced (but no Fine Gael cronies this time).
Finally, he could address the concerns of Ombudsman Peter Tyndall who has pointed out that water complaints are outside his remit.
Right now, however, the Government appears to be not waving but drowning. When a normally reliable footsoldier such as Fergus O'Dowd takes his finger out of the dyke, it is a sure sign that the floodgates are about to open.
Don't be surprised if they end up washing Enda Kenny's last few shreds of credibility down the drain.