To get anywhere nowadays I think you need both, it used to be just having a semi-sucessful mod or mods as the main part of your portfolio would open just about every door*, nowadays they want to see proof of industry appropriate training in the design/programming software as well as a portfolio showing you can put that training into practical use in a structured and professional manner.
* how I got in in the first place was from a couple of levels I made for a quake 3 TC and they weren't even that good really (tho ahead of the curve at the time).
* how I got in in the first place was from a couple of levels I made for a quake 3 TC and they weren't even that good really (tho ahead of the curve at the time).