It's hard to think the math through when no one knows the percentages.
In all likelihood, it lowers the chance for us winning the #1 overall pick, but raises the (still admittedly fairly long) odds of drafting both McDavid and Eichel.
You're very much overthinking what I said.
The only way for the Sabres to get the top two picks is for the Sabres/Islanders to win the lottery and the other to finish last. This likely increase the chances of that happening based on the teams rosters.
Yes, you're right for that
specific 2015 outcome of obtaining BOTH the 1st and 2nd pick, I agree the chances for the combined outcome are increased slightly, but ONLY BECAUSE the 30th team can pick no worse than 2nd.** Also, that slight increase in the combined outcome comes with a MUCH LARGER DECREASE in the probability of picking 1st and nth (but not 2nd), and therefore a correspondingly large INCREASE in the probability of picking 2nd and nth (but not 1st).
For 2015, I'd vastly prefer the much larger probability under the old rules of picking 1st the worse BUF finishes as against the much smaller increase in probability of picking both 1st and 2nd under the new rules.
**in 2016 (and I assume beyond), with top 3 picks in play, the guarantee of no worse than 2nd pick to the bottom finisher goes away. Then, scenarios for 1st & 2nd picks (i.e., combination events) become MUCH smaller, because they become the products of the individual probabilities. We'll figure that one out later...