In order to enter the U.S., the documents presented and the purpose and intent have to be compatible. If his purpose and intent are to visit only, and not to work for the L-1 petitioner, then he could enter as a B-2. However, it's hard to believe that anyone would really want to do that.
Is he not ready yet to assume his duties as an L-1? Does he still have things going on in his life or job outside the U.S. that must be attended to prior to moving to the U.S. Has the company in the U.S. set a start date long after the tourism trip would be over?
If he could prove that he's still working outside the U.S., and that the company in the U.S. doesn't want him to do any work in the U.S., then I suppose he could enter as a B-2, but it's certainly a departure from what is normally seen at a port of entry.Answer 2
Many people hold two visa's. If he was entering as a visitor using the L1 he might be refused. I like the fact that this person is trying to do the right thing. He can enter as a visitor using his B1/B2 visa.