andrea99 - 10:39 pm on Nov 22, 2005 (gmt 0)

Of course it is valid.

My "problem" is that AdSense just works better than anything else I try. Sure I continue to diversify but sometimes think that if I just put that energy into developing more AdSense revenue I'd be banking more money against the day that AdSense may falter.

Being in business is a constant stream of choices about scarce resourses; time being the most scarce resourse of all. Building upon something that is working well often makes more sense than trying something new and risky.