The victory sends Penallta six points clear of second placed Ystrad Rhondda, who leapfrogged Abercynon after a comfortable 30-11 defeat of Rhydyfelin.
Builth Wells's John Thurston was also in fine form as the fullback defied the poor underfoot conditions to scorch over for a hat-trick of tries against Newport HSOB. The speedster also notched 13 points with the boot to collect 28 of his side's points in the 43-7 drubbing.
Mountain Ash were brought back down to earth after their surge up the table when Treherbert outside half Gareth Roberts struck over a penalty a minute from time to snatch an 11-10 result while Ynysybwl had to come from behind to edge past Pill Harriers 13-5.
Abergavenny maintained their advantage at the top of Division Three East as the crossed for six tries in a 40-8 hammering of lowly New Tredegar. Will Johnson claimed a brace in the rout with Richard McCormack, Gareth Williams, James Williams and James Padgat also going over.
In the chasing pack, Garndiffaith were too strong for visiting Pontypool United as they scored four tries in their 24-12 win but Brynmawr made life far more difficult for themselves at Croesyceiliog where they missed five kicks at goal before sneaking an 8-6 triumph.
There was also a priceless win for Pontllanfraith who prevailed 20-8 over Senghenydd in a dog-fight between the bottom two.
Gwernyfed kept their necks in front in Division Four East title race with a 17-3 win a Risca but Abertillery remain in the hunt as they powered past struggling Abercarn 27-3.