First quarters rarely tell lies and like so many games this one was effectively done and dusted by the 17th minute when Shannon mauled their lineout all the way to the Dungannon line from fully 40 metres out to make it 13-0.
In truth, like so many AIB league games, the contest was probably decided before the kick-off.
In a season where, more than ever before, injuries and a realignment of priorities in favour of the provincial and national sides have disrupted selections, late enforced changes to teamsheets is fast becoming the afternoon's most accurate barometer of what's to come.
News that Paddy Johns had joined Tony McWirter on the sidelines on Saturday morning by an ear infection not only deprived Dungannon of their primary front-of-the-line ball-winner, and some sorely-missed bulk against Mick Galwey, Anthony Foley and co, but also of its heart and soul.
With their scrum in frequent trouble, and Allen Clarke struggling to cope with the blustery wind far more than his counterpart Mark McDermott, Dungannon rarely had a foothold in the match.
They had no answer to Shannon's lineout and especially their maul (which accounted for three of the home side's four tries), while on the rare occasions their pack sought to bulldoze their way over from close range they were sent shuddering backwards.
To compound their woes, David Humprheys had an off-day in front of Warren Gatland as he tried to force the game and made a couple of basic handling errors which were symptomatic of the blue and whites.
Shannon were also hit by injuries - no Alan Quinlan or Peter Stringer to begin with - but by comparison they have far more strength in depth. Whatever internal difficulties were plaguing them - and Pat Murray was clearly very much back in charge on Saturday - they seem to have overcome them and they began this encounter with the bit between their teeth.
Playing adroitly for the poor conditions, in front of about 2,000 spectators, Shannon inched their way the length of the field for their opening penalty. They followed it up with a couple of tries from lineout mauls - not so much walking the second one in but trotting up the field before Eddie Halvey burst out for glory.
Even when they opted for a close-in scrum as an alternative route to scoring, Foley took about three opponents over the line with him as he swivelled over from 10 out while Dungannon were down to 14 men because of Stephen Bell's sinbinning.
Anderson's temporary tactical replacement, bringing on substitute scrum-half Ashley Blair for winger Jonathan Davis, backfired when the Shannon think tank alerted the fourth official, who in turn notified Donal Courtney that Blair had to remain on the pitch for Davis when Stephen Bell returned.
With Marcus Horan, Galwey and Foley all having big games, and with such a dominant platform in the set-pieces, it seemed their bonus point would be secured by halftime.
In the event, Dungannon showed a bit of spirit and applied their continuity to good effect in preventing a rout, with Jonathan Bell crashing over on the blind-side of a scrum and Humphreys taking his kicks.
Shannon had rejected the opportunity of going for a fourth try early in the second-half when Conor Burke kicked a close-range penalty, and it seemed they might miss out when Halvey was in turn sinbinned just past the hour.
But while Murray admitted he would have been angry to miss out on the bonus point, he also explained they decided to go for Burke's penalty because they needed to score first in the secondhalf. They think most things out.
The value of the bonus points system was underlined in a lively finale, as Dungannon kept running from their line while Shannon upped the tempo in search of that fourth try. Noel Healy nearly sent Galwey over, and Healy nearly scored off Cormac O'Loughlin's audacious pass between his legs, before Colm McMahon was at the sharp end of another lineout maul.
In their all-conquering four-in-a-row, this was the type of game Shannon would simply have closed out at that isolated whiff of danger when Jonathan Bell's try made it 23-13. Nobody did it better.
But the benefits of the Super 12 points system were there for the crowd to enjoy in that finale, as Shannon, typically, just did enough to extract a maximum haul. Ever the minimalists again.
Scoring sequence: 5 mins: Burke pen 3-0; 7: Galwey try 8-0; 17: Halvey try 13-0; 28: Foley try, Burke con 20-0; 40: Humphreys pen 20-3; 52: Burke pen 23-3; 59: Humprheys pen 23-6; 67: J Bell try, Humphreys con 23-13; 75: McMahon try 28-13.
Shannon: Jason Hayes; J O'Neill, C McMahon, M Lawlor, J Lacey; C Burke, C O'Loughlin; M Horan, M McDermott (capt), John Hayes, M Galwey, J Langford, T Hayes, A Foley, E Halvey. Replacements: N Healy for Hayes (47 mins), A McGrath for T Hayes (66 mins).
Dungannon: J Bell; J Davis, J Cunningham, Alastair Clarke, T Howe; D Humphreys, S Bell; J Fitzpatrick, Allen Clarke (capt), G Leslie, R Stafford, K Walker, J Patterson, A Boyd, A Hughes. Replacements: A Blair for Davis (25 mins), P Curry for Patterson (74 mins).
Referee: D Courtney (Leinster).
