Heaving depends on the type of soil and its moisture content. You know your soil, so if you think that adding compost would improve drainage then it may well help but that should be for the whole bed and not just the planting hole because amending only the planting hole could theoretically make things worse if the amended soil is more water retentive and/or the heavier soil surrounding the hole prevents water from draining away. There should be less heaving in a drier soil.
I did actually break my rule and plant a few daylilies last fall. Kind of dreading what I will find when the snow melts!
