If you tried HDVSplit and had the same (negative) results, you can take Adobe out of the equation. Then it is either JVC or MS. Just trying to narrow it down to where you should complain.
Thanks, Harm. Now at the risk of sounding like a complete moron, and with great trepidation, I tell you this...
After working pretty steadily to resolve this issue yesterday and all of this morning, I decided to simply created a new project just for capturing. From previous experience, it didn't matter whether I chose an Adobe sequence preset or a Matrox one (I'm a MXO2 Mini user), because nothing I had tried worked. This time, with the firewire connected to a JVC GY-HD110 camera, set to playback, I started the tape running BEFORE I opened the capture utility. Low and behold, it is working. I hope that my luck continues for a second tape.
I am by no means an HDV expert myself, but what you describe smacks of a hardware/firmware issue with the JVC camera. It's as if the camera is not "talking" through the attached FW cable unless it's playing back, and if you start playback after Premiere is already "listening," Premiere doesn't "hear" it (apologies for all the double-quotes). When you're streaming video through the FW cable before launching Capture in Premiere, it is able to catch the stream and capture it.
That is based on little to no technological understanding of HDV, mind you
I have never used JVC, but I do succesfully capture HDV from either Sony or Canon. There are two flavors of HDV--HD1 and HD2. As I recall, Sony and Canon use HD2. It is my understanding that the CODEC is different. Since I've migrated upwards through CS3 to CS5, I've forgotten where I set this within Premiere. Also, the camera or deck must be in the HDV mode--the auto mode will not work. Also, you usually need to disconnect the FW before making a change between HDV and DV before it will be recognized by the PC.