I think alot of people use smcFanControl this way. Some may argue that any such use of fan control can shorten the life of the fans. While this may be true, the question is by how much. You may still end up upgrading to a new MBP before the fans ever fail.
If you want to avoid the issue all together you can get a regular lap desk or a cooling lap desk and leave the fans alone.
It's not that I am worried about any discomfort to myself because of heat. I am only worried about keeping the vital components in my mac in great working condition for as long as possible. If the fans go out, which i don't believe will because of my little use of SMC Fan Control, it is definitely a cheaper repair than if the cpu or other vital components were to go out due to long term heat.