Markets in everything: non-simultaneous trades

Via Al Roth, here is an NBA example which makes my head spin:

"Here is a more complicated example of a legal non-simultaneous trade:
a team has a $4 million Traded Player exception from an earlier trade,
and a $10 million player it currently wants to trade. Another team has
three players making $4 million, $5 million and $7 million, and the
teams want to do a three-for-one trade with these players. This is
legal — the $5 million and $7 million players together make less than
the 125% plus $100,000 allowed for the $10 million player
($12,600,000), and the $4 million player exactly fits within the $4
million Traded Player exception. So the $4 million player actually
completes the previous trade, leaving the two teams trading a $10
million player for a $5 million and a $7 million player. From the other
team's perspective it's all just one big simultaneous trade: their $4
million, $5 million and $7 million players for the $10 million player. "