My speed-matching was a success. I set the IM F3 and Proto BL2 on parallel tracks and adjusted the acceleration, deceleration, start speed, top speed, even max current draw, until they ran like near-identical twins forward. Backup was a different story as we find early on in the hobby, some locos run better backwards, thrust washers notwithstanding. (Be sure to have clean track and wheels, for best results.) Also, the BL2 has a near-imperceptible hitch in her giddy-up I can't remove but still MUed nicely. Added benefit -- speed matching seemed to smooth current draw and reduce voltage spikes.
I made sure the HC and LM programs were up to date, however, after I did I noticed that the HC still indicated V1.0 for the LMs, even though I updated with the newer update on the Ring site. Hmm...