It does not matter where you're stopped, it matters where you were when the officer obtained your speed. You can obtain this information through disclosure requests.
1. File the ticket for trial, request for the officer to be present.
2. Once you receive your notice of trial with the trial date, request disclosure: http://www.ontariohighwaytrafficact.com/topic2959.html
3. Review the disclosure, and choose whether you want to plea-deal or go to trial.
Unnecessary slow driving prohibited
132. (1) No motor vehicle shall be driven on a highway at such a slow rate of speed as to impede or block the normal and reasonable movement of traffic thereon except when the slow rate of speed is necessary for safe operation having regard to all the circumstances. R.S.O. 1990, c. H.8, s. 132 (1).
I've seen some evidence that there may be enforcement of S132 in Ontario but it has to be in an incredible situation: https://twitter.com/TPSmotorsquad/statu ... 3063763969
S128 is low hanging fruit, and those are the type of the aggressive driving charges that voters want to see. It's also not illegal to drive 60 in an 80 zone, especially if you're driving for the conditions.
R. v. Cianchino, 2010 ONCJ 298 (CanLII) - defendant drove 50km/hr on the 407 and caused a collision, ended up being found not-guilty.
But remember you do not have to testify against yourself, so there are others ways to win without having to take the stand.
I would choose the NOT GUILTY option and request a Trial with the officer present. Once you get your notice of trial, you will then request disclosure (include notes from ALL officers involved, radar manual, audio/video).
Once you get disclosure, post it here for us to look at.
Can you scan and post your ticket (with personal info blacked out)?
+++ This is not legal advice, only my opinion +++