For each formdata node it is not quite uncommon to have over 50 formfield nodes. This leads to a huge amount of form nodes, quite often in the many millions, which makes several operations quite slow, like (re)indexing, cleaning up and can take up quite a bit of resources in the database or in memory for queries.
Would it be possible to store the formfields directly on the formdata node and hence slashing the number of nodes by more than an order of magnitude?
I'm not 100% sure if this is functionality that is actually built in the HST or in some other project. In the later case, please move the issue to the appropriate project.