This should be no surprise to a founder that your friendly neighborhood VC wants you to be spending 100% (actually 120%) of your time and attention on your company. If this paragraph sneaks its way into the term sheet, the VC has either been recently burned or is suspicious and / or concerned that one or more of the founders may be working on something besides the company in question.
Brad Feld has been an early stage investor and entrepreneur since 1987. He is currently a Managing Director at Foundry Group. Prior to co-founding Foundry Group, he co-founded Mobius Venture Capital and, prior to that, founded Intensity Ventures. Brad is also a co-founder of TechStars.