Nick - agree with you on the "picking players who will improve" concept. I guess what I would say to those doubters - not yourself - who don't pick Cross because of this mantra is this: not everyone you have will, or can, improve on their average and sometimes its good to pick a player you know will nab his average, or close to it, every week.
The way I see it, losing 3 premiums in one round is the same as losing 2 in round and 1 in another, provided they are all on different lines and you use the same rookies to cover them. It'll look like you're getting a worse score for that week, but that will be balanced out by getting a better score on another week when you don't need to cover that midfield spot. Its when you lose multiple premiums on the same line that you are dipping into your bench depth and could potentially get a worse score.