re: Writing a check against a credit card account - is there a catch?

Yes, but you can't do it unlimited times

Also you described getting the money, now put into reverse and do it again, you are at 50 an hour, might be great for you but it is a waste of valuable time to me just as it would be at 100 an hour for that short a time period.

Judging by the amount of "if's" in your post you must be real sure about it which means more time researching, whoops now you are down to 40 an hour, see how valuable time flies.

This is not even allowing for the unforseen.

Now for the potentially bad, should the need to borrow money arise the dent in credit is likely going to cost you.

All just my opinion for me in my situation, yours may be different.