Re: idle with trim up
As long as you don't exceed the trim limit via the standard 'trim' button. If you use that button and nothing was rigged up to bypass the limit sensor, you are good.
Trouble arises if you use the trailer trim button to exceed the trim limit or if you have a setup that bypasses the normal trim limit.
(The trailer trim exceeds the safe operating range for the drive. Hey, you can stress the joints too much under any kind of power).