Try increasing the RAM used for scene detection in capture prefs from 25% to 80%. Well known fix for this.

Alternatively, use the free program HDVsplit for capture. Horses for courses you know.

Edit
Use WinDV for DV tape or HDVsplit for HDV tape.

I might give those a shot later. On FCP at work I got the same problem -- it would cut it a few times, similar spots to where Vegas did. Unfortunately I was given a tape we normally don't use and they all seem to have issues which is why we switched over to Sony, so it's probably partially the tape.

I would also like to point out FCP is garbage when it comes to iffy timecode from tape. Every now and then I get a tape so badly messed up that FCP does a poor capture of it and usually my next step is to use iMovie to capture, but if that doesn't work I'll bring the tape home and Vegas will capture the whole thing no problem. Sure the tape glitches might still be there a little, but it doesn't seem to phase Vegas.

Yes I get this a lot using the HDV capture tool. Yes part of it is a questionable tape, but I still can't understand why the capture tool would break a clip into pieces if scene detection is turned off. It never reports any dropped frames, but it still cuts up a single take on the tape into 2 or more clips (as if scene detection was on, and there was actually a new clip started on the tape as per date/time stamp).

I'll try the increase in RAM usage in capture settings, although I don't remember seeing this setting in the HDV capture tool settings.