Freeze Groove Agent drum tracks to save resources, or not?

Some of my projects are quite resource-intensive, and when it’s time to record vocals, I need to minimize resource (CPU) strain to have the smallest possible buffer size (256, in my case) to keep latency under the perception threshold so that it doesn’t throw the vocalist off.

So I freeze all VST instrument tracks (and render-in-place effects-heavy audio tracks) to free up CPU.

I also do that to my Groove Agent tracks (I have separate tracks for each drum, i.e. one track for the snare, one for the kick drum, one for the hi-hats, and so on).

However, it is not at all clear to me whether that actually makes sense. I could imagine that Groove Agent triggering a drum sample is extremely light on the processor, and possibly uses less resources than playing back a frozen track (which, esp. for drum tracks, is mostly playing back nulls).

Has anybody ever done any testing to figure out whether we’re better off freezing Groove Agent tracks, or not, if we want to minimize Cubase resource usage?