yeah, IMHO that technician guy has one of two reasons (or both) for requesting DVCAM recording on DVCAM tape:
1) not mix the tapes. If it's DVCAM, it's Sony. If it's DV it can be Panasonic, Fuji,..whatever. As Adam Wilt says, you can have bad head glogging problems when mixing different vendors' tapes. If it's a big system, such a small problem as head glogging can be a real pain in the ***.
2) his VTRs don't enter edit mode when DV format is used on DV or DVCAM tape.
Anyway, it would be better to talk these problems through, not to invent some weird reasons for programme producers.

Scott, hope you find a way out of this situation.

regards, Margus

That is not entirely correct. The tape formulation is different. The cassette is a bit more rugged and precise. It also costs about 4X more.