Not to butt in, but Rosoco brought this into a league I'm in with him and lakeviewdave sent me a PM asking for my opinion/advice, so I thought I'd at least share the reason the rule is written the way it is, as I was in the league that first implemented it and know the whys and wherefores:
Roscodog wrote:Saw this posted in another league and I like it, I've been thinking of something like this for a while now. I've never totally understood the rationale for the rule and think it can be simplified. Since I've taken over this league, I don't think its ever been enforced anyways.
The logic was this,( and I know 'cause I know the guy that wrote the rule, sandlotshrink, it was written and discussed for USKL and has become adopted by most of the keep leagues here on the site.)
You are using the assumption that every team has draft picks in 1-10 (or 15) rounds regardless of cuts, which can lead to a situation where someone trades a pick even though they have a full roster and wouldn't be using that pick. So the rule was written to ensure you only get picks for cuts. So even if you have a roster of less than 40 due to unbalanced trade trade you still need to make enough cuts to account for the draft picks you've traded.
The real problem was this, and this is why it was enacted, we had a manger that made his ten cuts, which can lead to a situation where someone trades a pick even though they have a full roster and wouldn't be using that pick. but was done drafting for his team in round 7 but then during round 8 of the draft, he traded his 10th round slot to another manager for a future draft pick even though he already had a full roster, which none of the rest of the league thought was fair. That's the situation the rule was written to prevent. So long as there is a caveat that a slot can't be traded once a roster is full I can see making a change
The other reason the rule helps is it has the added benefit of forcing guys to make cuts thus adding to the player pool for the draft, which, quite frankly I've found lacking in some leagues, and so I've made adjustments in my later leagues to the supplemental drafts and prospect drafts to also help the Spring draft player pool.
Thought this might at least give you some perspective and show why the rules was written.