as long as you set it to clear lineup after use you should be fine, i have used it every year
I never used that so I have to take a look to see how it works
My experience with two-way guys is that you will get maximum starts at pitching and hitting if you set the player position to SP, put the pitcher in the rotation, and also put the player in the daily lineup and set a backup to play every 4 days. If you set the backup to "If Starter Tired", the backup will play too much. Using this you can get starts at pitcher and in the field/batting lineup and see how the player progresses.
I've never had a guy make it to the majors this way playing both, they always end up going one direction or the other. For me, usually if they can pitch well, I end up using them as a pitcher. And if the league has no DH, that guy can be worth some WAR if he's a good hitter going every 5 days in the rotation.
You could at least try this for a few weeks and see how many games the guy is playing at each position, and how many ABs.