In wet and windy conditions at Rosbrien, Bruff had the blustery elements behind them in the first half and they established a 12-0 half-time lead thanks to four penalties from Brian Cahill.
Cahill's opener in the third minute, from a few metres inside his own half, was the best of the lot and Bruff's territorial dominance grew as he added to their tally after 13, 18 and 36 minutes.
Try-scoring chances were at a premium for the visitors, and handling errors and poor decision making spoiled some good approach work for a Bruff side that deserved a try for their efforts.
Still, Old Crescent's forwards excelled at the breakdown and their commitment in defence was top notch and turning around with the wind in their favour, the Mark Ryan-skippered home side looked good for a comeback on the scoreboard.
The second half was scoreless until Woods landed his first penalty in the 56th minutes, and his second soon followed.
Bruff's defence was holding up well and when Woods fired wide with his next penalty attempt and the 80-minute mark arrived, the visitors looked like they had sealed the deal.
However, there was late drama when Crescent rampaged forward and in deepest injury-time, centre Billy Leahy speared through a midfield gap to touch down to the left of the posts.
With the wind difficult to read, Woods was left with the conversion kick to win the game for Crescent. His effort looked to be curling over before it struck the post and fell away, allowing Bruff to clear the ball to touch and celebrate with much relief.
Leaders Lansdowne registered another bonus point success when they ran out 30-0 winners over Clonakilty at the RDS. A Kurt Morath penalty was all the West Cork side had to show for their efforts, while Dominic Ryan, Willie Earle, Ross McCarron and Matt Healy helped themselves to tries for the in-form hosts.
Highfield posted their first win of the campaign at Gibson Park, edging out Malone on a 20-18 scoreline. John Murphy, Aidan Rees and Fergus Gately scored tries for the victorious Corkmen, with Mark Hill and Stuart Wilson touching down for Malone.
At Deramore Park, Belfast Harlequins maintained their unbeaten run with a 15-8 defeat of Greystones. 'Quins were 5-0 ahead at half-time, with winger Rory Blake-Knox getting over for a try off a Chris McCarey-inspired attack.
Team captain Neil McComb, a current member of the Ulster squad, excelled in the lineout and 'Quins pushed on, two minutes into the second half, when flanker Andrew Gillespie shrugged off two tacklers and made it over for a try which New Zealander John Mills converted.
Mills added a penalty on 46 minutes but Greystones fought back well in the final quarter, gaining a losing bonus point thanks to a Barry Lynn penalty and a 78th minute try from Killian Keogh.
Corinthians made it two wins on the bounce as they emerged as 18-11 victors over Bective Rangers in strong winds and driving rain at Corinthian Park.
Eugene Murnane's side trailed 11-3 at half-time, having faced into the elements. Bective ironically had a try from lock Mark Hennelly and two penalties from out-half Cormac O'Beirne, two former Corinthians clubmen.
Corinthians hit back, six minutes into the second half, when breaks by Wayne Williams and Pat Cunningham got the hosts on the hoof and centre Eoin Griffin was able to cross in the corner for an unconverted try.
Out-half Shane Mullaly landed his second successful penalty on the hour mark and while a late converted try from scrum half Mike Roche sent Corinthians ahead, the Galway outfit had to dig deep to prevent the visitors from scoring an injury-time try - indeed Bective was held up over the try-line in the dying seconds.
Elsewhere, De La Salle Palmerston, Terenure College and Thomond all secured away wins, Thomond's being the most eye-catching of the lot given that they had lost to UCD the previous week in the AIB Cup.
Beaten 21-15 at home in the cup's second round, Thomond gained revenge on 'College with a superb 32-16 win at Belfield.
A well-worked try by Darragh O'Neill fired Martin Ryan's Royal Blues into an 8-6 half-time lead, after two penalties from Noel Reid had initially put UCD ahead.
Finding an extra gear with the wind at their backs, Thomond made it 18-6 when out-half Declan Cusack converted Warren Kelly's try from an interception and Cusack, who has taken up a training contract with Munster, tagged on a penalty.
Further tries from Declan O'Connell and Darren Clancy sealed the bonus point for the Limerick men and had them out of sight, and late five-pointers from UCD's Terry Jones and Kevin Croke were only consolation scores.
DLSP also maintained their 100% start to the league run, battling their way to to a 28-17 triumph over Dublin University. South Africa half-back Dustin Jinka, in his second season at Kilternan, landed three penalties and converted two of 'Salmo's three tries.
At Donnybrook, Terenure College scored a 26-10 win over hosts Old Wesley to move up to sixth in the standings. A 60-metre intercept try from Wesley winger Ross Johnson closed the gap to 13-10 at half-time.
But 'Nure, who were well-organised and controlled possession for long periods of the game, grabbed their second try when a brilliant break by man-of-the-match David McAllister exposed the Wesley defence and young loosehead prop Andrew Buckeridge finished off the move.
Former Leinster out-half McAllister added the conversion and kicked a 55th minute before full-back Adam O'Loughlin launched a neat drop goal between the posts to complete a pleasing afternoon's work for 'Nure.
AIB LEAGUE DIVISION 2 RESULTS: Saturday, October 24
Belfast Harlequins 15 Greystones 8, Deramore Park
Corinthians 18 Bective Rangers 11, Corinthian Park
Dublin University 17 De La Salle Palmerston 28, College Park
Lansdowne 30 Clonakilty 3, The RDS
Malone 18 Highfield 20, Gibson Park
Old Crescent 11 Bruff 12, Rosbrien
Old Wesley 10 Terenure College 26, Donnybrook
UCD 16 Thomond 32, Belfield