Low-Latency Mode / CPU

This is more of a confirm-how-this-works for me rather than a problem, since I think I have this figured out, but please bear with me.

I just upgraded from a 2011 iMac i7 to a 2018 Mac Mini i7. So: big CPU upgrade. I have a template where all of my tracks are routed to submix buses, which are then routed to a Main Out submix bus, which then goes to the Stereo Out. I generally have inserts on the submixes and the main out mix, but not the Stereo Out.

On the old machine, if I needed to re-track a part after I'd started mixing, I would enable low-latency mode, Logic would route the recorded track directly to Stereo Out (around latency-inducing plugins), and things would be fine. On the new machine, doing the same thing kept the routing and spiked a single CPU core (and, in the case of multiple instances of iZotope Neutron 2 across the project, caused overloads).

I think--and this is the question, if there is one--this is because the default limit for Low-Latency mode is 5ms, and with the beefier CPU, those CPU-heavy plugins were reporting less latency than that. Decreasing that latency limit to 1 or 2ms seems to have fixed the problem, but I'm not entirely sure.

Does this make sense to anybody else? Is my read of the situation right? Thanks!