Windows – Why do netsh ip delete commands run so slowly in Windows Server 2003

So a coworker accidentally added an entire /20 (~4000 ips) to a Windows 2003 Server.

I generated a simple batch file with all the necessary lines to remove these IPs. The commands do work and remove the IPs as I want, but the problem is they take around 3 to 10 minutes to execute each line, and the CPU is staying > 90% utilization, svchost.exe and lsass.exe seem to be eating up the most cycles.

Anyone know why these netsh commands are taking so long to execute?

Example:

netsh interface ip delete address name="Local Area Connection" addr=10.10.150.24