[Falstaff]

A few reasons...
1) I've buffed poison quite a bit (healing mitigation) and I wanted this to be balanced around the fact that you must expend mana to get the benefit (cast the Poison spell) otherwise I worried it could be overpowered.

2) However, single handed blade weapons are generally too weak right now. Ignoring SDKs etc. for the time being that is (will probably have to do something about them later). So it was a good indirect way of giving these weapons a buff such that they serve a purpose, also it adds some complexity to the "warrior" element of PvP which may be good for people who want to go down that path.

I wanted to make as many spells and weapons useful as possible, but I didn't want to overpower things, so I've gone for the approach of trying to give things unique purposes - in this case single handed blade weapons serve the purpose of being a cheap and easy way to poison enemies without expending your mana, but bigger two handed weapons continue to serve the purpose of being primary damage dealers and having a more reliable damage output.

if this is the case maybe you can consider making poison last longer. For instance deadly poison should last longer than it currently does.