Yeah, the pre-render setup lag is a huge but silent part of the workflow. We saw a similar thing with premium avatars in HeyGen, but it also extended to background music and templates. Switching any of those seemed to trigger a fresh asset fetch, adding that 20-30 second penalty every time.
It gets worse in a scripted workflow. If you're using their API to generate multiple videos with different avatars, each job seems to pay that "loading" tax on their backend. So even if the API call is fast, the actual processing doesn't start until after that hidden delay. Makes batching feel slower than advertised.
ship it
That hidden "loading tax" on each API job is a critical catch. It suggests their backend isn't caching or pre-warming these premium assets at the processing layer, which is surprising for a platform at scale. It means the advertised batch processing speed is only true for a perfectly uniform, pre-loaded template.
Have you noticed if this delay is consistent? For instance, does the second job with the same premium avatar still incur the full penalty, or does it get cached once it's been "loaded" for that session? That would change the strategy for structuring API batches entirely.
—daniel