You are correct to say the numbers aren't 100% correct.  However, I believe they are as good as can be with available data.

I keep my eyes open online and have a couple 'sources.'

Workout bonus - A form of a LTBE.  It is what it seems.  A bonus based on a player working out.  All players receive money to workout - per the CBA between the NFL and NFLPA.  However, some players have additional bonus money included into their contracts.

LTBE - Likely to Be Earned.  Incentive-tye bonuses (could be an individual-based incentive or a team-based incentive) based on an incentive.  The CBA clearly defines what bonuses are LTBE and what are NLTBE (Not Likely To Be Earned).  For the salary cap purposes, incentives deemed LTBE count towards that year salary cap.  Incentive bonuses deemd NLTBE do not count towards that years salary cap.  HOWEVER, all money paid to a player eventually counts toward the cap.  Therefore, if a player in 2007 had a LTBE bonus (threfore, it counted against the 2007 cap) and this bonus was NOT earned the team gets a credit at the end of that year.  ON the flip side, if a bonus was a NLTBE, but was earned would result in a salary cap minus at the the end of the year.  This is why all teams have an adjusted salary cap...the adjustment is the difference between LTBE that were NOT earned and NLTBE bonuses that were earned (atleast, this is a very basic explanation...the CBA is not basic).

Deion - Is something )named after Deion Sander, that prevents teams from backloading contracts with the anticipation of an uncapped year.  Deion charges only apply when there might be an uncapped year.  Prior to the 2006 CBA extension, the was the possibility of an uncapped year.  The Deion Rule prevents teams from structuring contracts with more than a 30% increase in salary cap value...from one year to the next.  AGAIN, THIS IS ONLY WHEN AN UNCAPPED YEAR IS A POSSIBLITIY.  Teams had to adjust players' salary cap values (with a Deion credit) to be in compliance with the Deion Rule.  Now, the teams are getting the credits back.  http://www.steelersalarycap.com/player/BenRoethlisberger.htm   Ben had to increase his cap value...now those increases are being given back..hence the negative Deion Charge.  Again, the CBA is a bit confusing, this is just a quick explanation.

If a player is cut, their base salaries do not count.  (there are exceptions...)  If a player is cut, any money already paid to that player still counts...any money not paid does not count (atleast most of the time - not always).  Typically, base salaries are paid in 17 equal "checks."  Starting the first week of the season...16 weeks in a season plus one bye week.

A fellow cap guru does keep track of all teams salary cap...he has them for all to see.  They are all excel spreadsheets that need downloaded.

http://www.ianwhetstone.com/football/cap.html

Oh, he is a huge steeler fan as well.  We email info to each other wit regards to cap data.

Basically, per the CBA, any incentive type bonus given to a player during the season automatically counts as a LTBE.  

So the Steelers could sign Ben to a new contract in week two of the season.  The new contract could be exactly the same as his old one (with regards to his base salaries and such), but have one new incentive...say if Ben gets 89 special teams tackles he gets $14 million.  Now, Ben doesn't play special teams and would never earn that bonus.  However, IF THE STEELERS HAD $14 MILLION OF CAP SPACE (the key to this loop-hole), Ben doesn't earn the LTBE; therefore, it counts a +$14million towards the Steelers adjustment for the next year's salary cap.

The owner wanted to fix the loophole during the 2006 CBA talks.  The NFLPA, did not want it fixed.  Apparently, the NFLPA won with regards to the loop-hole.