I was heating up a Hot Edge for use in Tier 1 Lockdown, and noticed a few things:
1) On Depth 1, the third combo hit deals noticeably less damage than the first two, at all heat levels
2) This fixes itself on Depth 2 and deeper
3) The Fire effect from the third combo hit deals slightly less damage than that from the charged attack (Tested on Jellycubes in a Danger Room)

Weird! Something strange going on with the depth scaling? ...Wait, why is a 1-star weapon even scaling at all in Tier 1?

This actually has a couple implications for Lockdown: if the arena counts as Depth 1, you might not actually want to use the third combo swing on the Hot Edge and its electric equivalent, the Static Edge. (Though there is particularly satisfying if you land the status effect on a Recon and he hits his shield button on reflex... and then the status damage breaks his cloak.)