Is historical reconstruction dangerous when evidence is missing?

Is it dangerous for historians to fill gaps left by a missing core document with their own analysis?

It is dangerous when the reconstruction is presented as fact. Historians should identify their evidence and make clear which conclusions are their analysis.

A missing core document can leave a historian with surrounding evidence but no conclusive explanation. Research can still assemble and compare those sources to support an interpretation. That differs from an immediate opinion based on whatever comes to mind. The risk arises when the resulting interpretation is presented as an established fact. Clear wording should let the reader distinguish the evidence from the conclusion drawn from it.