Triathlon training can follow quite a traditional pattern of base, build, peak, taper, race, followed by the off-season. And this does work as it follows a progressive building structure, but what you do in those phases doesn’t need to include the same old tried-and-trusted sessions
While the off-season is a time for a bit of evaluation, recovery and focus on technique, it doesn’t mean that you can’t
do brick sessions, as they can be included at any stage of a tri season. The key to using them correctly is that their intensity or duration should be appropriate for the stage of training.
I’d suggest including a brick session every 2-3 weeks in order to keep reminding yourself what it’s like to train one discipline after the other. But these sessions can take different structure and should be done with a focus on low-to-moderate intensity, after all this is the off-season. So maybe a 50min fat-burn bike followed by a 10min run focusing on posture and technique, or a steady 5km run followed by a 20km bike with some high cadence intervals.
One very worthwhile brick session to include is a run off the bike to nail down your run pace. Very often in triathlons, the first 20-30% of the run stage is too fast and then the athlete fades, but with practice you can develop discipline to hold back the run pace and then build as the run progresses.