If there was criticism to be made of this spectacular game then it would centre round critical lapses in defence by both sides, that allowed the likes of Thomson and Melrose debutant, Lee Jones, to score with greater ease than might have been expected.
But that is minor point. This was a thrilling game with high-quality attacking rugby that again underlined the premium value provided by this layer of Premiership rugby.
Melrose looked to be in total control when they led 38-10 at half-time, Gary Elder having opened the scoring with a try out wide, and then Jones, Thomson and Dodds each with a first- half brace bulging the home scoreline. Heriot's only reply in try terms had come from a fine effort by Struan Dewar but, far from disintegrating altogether, the Goldenacre men staged a spectacular rally after the break begun with a try after only 20 seconds from hooker Scott Burnett.
Peter Eccles added another from close range before Thomson completed his hat-trick to calm Melrose nerves.
A try from the impressive James King, playing against his former club, gave Heriot's further hope of a comeback but again Melrose stopped the rot with a Dodds touchdown.
Max Learmonth capped a good display with Heriot's fifth try but it was left to Lee Jones to bring the curtain down on the show with a fine solo effort to restore Melrose's lead in the championship race.
Scorers: Melrose: Tries: Thomson (3), Dodds (3), Elder, Jones (2). Cons: Wight (5). Heriot's: Tries: Dewar, Burnett, Eccles, King, Learmonth. Cons: Wilson (3), Goudie. Pens: Wilson.
Melrose: F Thomson; C Anderson, J Murray, A Blair, L Jones; S Wight, R Chrystie; N Little, W Mitchell, G Holborn, G Elder, R Miller, J Dalziel, G Runciman, G Dodds. Subs used: G Innes, N Beavon, H Mitchell, S McCormick, C Jackson.
Heriot's: C Goudie; G Bryce, M Learmonth, J King, M Nimmo; G Hunter, G Wilson; A Dymock, S Burnett, G Cameron; CJ Osazuwa, J Hill; P Eccles, S Dewar, J Syme. Subs used: K Bryce, W Blacklock, A Spence, M Goldie, R Mill.
Referee: C Rudkin.