I recently read an article in which the author considered it a near-certainty that the Phillies would've snagged two solid draft picks had Ryan Howard departed as a free agent after the 2011 season. That seems plausible on the surface - we know the Elias rankings don't use sophisticated numbers, and Howard seems like he would be a Type A lock.
However, a check of the 2008-09 Elias rankings for National League first basemen and outfielders shows that Howard ranked 23rd in the group at 76.296 points. He's a Type A, but the 27th-ranked player, Skip Schumaker, starts off the Type Bs at 69.394.
Several years ago, ESPN's Keith Law revealed that each league's 1B/OF groups are ranked based on five stats: plate appearances, batting average, on-base percentage, home runs, and runs batted in. Even though Howard tallied 1403 PAs, 93 HR, and 287 RBI over 2008-09, his pedestrian .265 AVG and .349 OBP knocked him well down the rankings. If Howard's 2010-11 production slips, he could easily be a Type B. Elias' formulas might not be the best way of ranking players, but they're part of the fabric of many multi-million dollar decisions. Looking ahead, the current collective bargaining agreement expires on December 11th, 2011, and we don't know if the formulas will be revamped.
Even if Howard did get Type A status, would the Phillies have offered arbitration? We've seen plenty of instances where players coming off good seasons were not offered arbitration - Johnny Damon and Randy Wolf are two recent examples. And there's always the chance the player accepts, like Rafael Soriano, Rafael Betancourt, and Carl Pavano did recently.
If a team makes it all the way to the point of a Type A free agent being offered arbitration and declining, there's a chance the draft picks gained aren't great. Look at the Blue Jays, received picks #34 and 80 for Marco Scutaro this year because the Red Sox also signed John Lackey. Scutaro's Elias number of 83.069 was just below Lackey's 83.865 figure. In the most extreme example, the Jays received picks #37 and 104 when Type A free agent A.J. Burnett signed with the Yankees a year prior. You're at the mercy of which team signs your free agent.
The point of all of this: you can dream of getting picks #19 and 33 for your big-name departing free agent, like the Astros did for Jose Valverde this year, but many factors can derail the plan along the way.