Count me in the group that says “Have fun, go for it.” Of course, I’m also in the group having fun, and going for it. I’m also a “born in the water” kind of guy, with lots of experience.
I live in a neighborhood with pond/small-lake access, and routinely cross the 1/2 mile or so of lake, and return.
From the hypothermia link:
Water Temperature (F) Expected Time Before Exhaustion or Unconsciousness Expected Time of Survival
50° – 60° 1 – 2 hours 1 – 6 hours
60° – 70° 2 – 7 hours 2 – 40 hours
70° – 80° 3 – 12 hours 3 hours – indefinite
> 80° indefinite indefinite
I’m just not worried about survival time. If I can’t do the distance in the 1-2 hours available in 50-60 degree water (which would be too uncomfortable for me to spend that long in anyway), then you’re not what I’d call “a strong swimmer” in the first place. I assume a strong swimmer covers about 2 miles/hr, so you’d be doing each stretch in 30 minutes or so. (semi-backed up by the following data What is the average time to swim a mile? - Answers) If you’re cold at the other side, take a break. If you’re tired at the other side, take a break.
I’ve had one “panic situation” in the water during my 35+ years of swimming, and that came from running out of air diving, at about 15’ on my way up. The panic came due to the slight negative boyancy at the surface at the end of the dive, along with the inability to suck more air at depth. 20 seconds after surfacing, I had my vest inflated, and I was on my way back to the boat. This was not my “normal swimming” and only my 2nd dive outside of my classes. (FWIW, the gauge was WAY off. >500lb indicated, nothing coming out of the regulator. The dive master, who owned the shop where we got the equipment agreed that it shouldn’t have happened the way that it did). Even in the choppy water, with weight on my back/belt, I handled it fine. I don’t want to have it happen again, but I was prepared. (Like Batman).
If my wife was asking the same question, I’d have a different answer for her, as she’s a “good” swimmer, but not someone that I’d lump into the “strong” category in the water. You have to decide if you’re comfortable with it, and if you have any other modifying factors, such as injury, impairment (chemical or otherwise), skill level, and conditions.
I won’t dive my myself, though there is a growing segment of the diving community who are embracing the idea, and SDI is offering a certification course (http://www.diveglobal.com/special/solo.asp). I won’t be signing up for it, but there are folks who consider it “safe enough.”
On top of the water, I’m comfortable alone, and would get very little swimming time if I was required to have a buddy. Under water, is WAY out of my element, and I’m not comfortable enough to even consider it.