SWIM 2X A DAY?

Sure - but make sure you're doing it with good form/technique, otherwise you're just reinforcing bad habits, and frequently.

Remember, though - triathlon is all three sports...

I used to swim competitively in high school. 3 mornings a week, 5 afternoons a week. I was fast, could swim long distances fast, but ultimately damaged my shoulder. I couldn't swim for several years due to rotator cuff and bicep tendon issues. I still have to be careful, I had to cut my swim short this morning because I could feel the bicep tendon flaring up. This is 14 years later. I can only swim every other day for the most part or my shoulders start aching.

That said, it is doable to swim 2x per day, but you're better off swimming less and making the time you spend in the pool count. Lots of drills, maybe get a coach to get your form critiqued, etc. Definitely work on quality over quantity and be careful of any hints of overuse injuries. It's just as easy to get an overuse injury swimming as it is biking, running or anything else.

I should have stated this would just be every now and then when the schedual permitted or the weather was something I did not want to run or bike in...

Well I'm assuming you're new to swimming, That being said, I know for me when I first started swimming about 3 months ago I went just 3x/week and tried to add another day but when ever I did my shoulders would start to get sore. I went back 3x/week and no more issues other then weeks if I try to swim on back to back days. So for me 3 times a week for about an hour is the most I can do, soon I'm gonna try and add another day because I think my shoulders have gotten stronger.

Basically from my experience I would say you can try it but if you feel any kind of soreness in your shoulder give it some more time between workouts.

It's a GREAT idea!