emails get sent via cron, even if I don't want them to

I have the falowing settings
Use cron to send newsletters: unchecked
Cron throttle: 2000
Log emails: checked

I have a newsletter with 2000 subscribers. I look in the log, and I see the newsletters are sent in batches of 400
400 emails sent in 204.9 seconds, 0 failed sending.
Sending interrupted: PHP maximum execution time almost exceeded. Remaining newsletters will be sent during the next cron run. If this warning occurs regularly you should reduce the Cron throttle setting.

I don't want to use the cron because of 2 reasons:
- even if I has setup the cron to run every 10 minutes, the email batches seems to be sent every hour. I need them all sent at once
- there's a bug with simplenews, in that it uses administration theme in the emails. I've set it up so the emails are formated corectly, and if the emails are sent via cron, the theme will change to front (and this is not tested).