I don't see how it would be a problem as long as the temperature stays low.
Mobile VRM's aren't designed for 24/7 stress at 100% (or more if overclocked). The ventilation is designed expecting normal pauses every now and then.
Notebooks also need to be stable on 24/7 stress. THere are desktop machins which fail at permanent load and there are notebooks which fail.
My notebook with t7400 and Nvidia 9700GT is old, but it can stand 24/7 load too.
THe temps are fine, in contrast to the HD5850 in my mining ring, its stable too, but becomes very hot.