Trying to determine why a plan changed with a syntax change
Implicit JOINs were converted to INNER JOINs.
@SQLTrooper is also correct in that the new plan, without the lazy spool, saves an enormous amount of IO. The lazy spool rewinds more than 43k times, causing 10Gb of data churn. By avoiding the lazy spool, MSSQL is able to greatly improve the execution time of the query.