The city side had posted a win at Torrance House earlier in the season but the suspicion remained that there was less between the sides than 17-0 suggested, as Accies had been able to field a number of first-team players who had opted not to travel that day to Inverness.
It was therefore a twist in that it was EK this time who took additional first-team firepower with Paul Rosie in particular benefiting from additional game time in his return to fitness.
The game was won in a first half in which the EK pack were rampant. The Rosie brothers in particular proved hard to put down and, with their ability to offload in the tackle, gaps appeared all over the field.
Scrum-half Sparky Ellison was the chief beneficiary of the power up front and his breaks around the tackle situation were a constant feature of the contest, at least until his legs gave out in the second period.
EK were well served by the 16-year-old contingent in the side, with Chris O'Neil, Glen Neilson and Scott Aitken showing well up front, and Bob Ferguson giving his usual physical display in the backs.
First half tries from Dave Rosie and Robbie Greenfield gave East Kilbride a comfortable cushion and a second-half score from replacement Sandy Bruce put a little gloss on the scoreline.
Accies remain comfortably atop the division but have now lost twice, as have EK, who have played five games fewer. Where Accies retain the advantage, though, is in bonus points accrued, and essentially have a one-win cushion because of this. If they take their remaining three games, then there is little EK can do to wrestle the title from them.
This Saturday 20 Feb, the 2nds host Strathendrick, kick off 1500.
TEAM: 1. Lubo Turnbull, 2. Dan McQueen, 3. Chris McLellan, 4. David Rosie Jnr,5. Glen Neilson, 6. Dennis Aitken, 7. Chris O'Neil, 8. Paul Rosie, 9. Mark Ellison,10. Bert Blackwood, 11. Dave Cowie, 12. Gordon Stevenson, 13. Craig Ferguson (II),14. Robert Ferguson, 15. Robbie Greenfield.
Replacements: Scott Aitken, Sandy Bruce and Stevie Keir.