Thanks for the question, and it does seem like a bug that VSF links would work with supported Xcvrs, but not with a 10G DAC cable.
As noted earlier, only supported Xcvrs, not Unsupported ones.
I'll alert the team to log this as a bug -- no promises on when it will get fixed, but duly noted.
To answer the question of if the HP X242 DAC cable is supported, yes it is - and works well for local connections.
NOTE: for the 2930F, a 10G DAC will only work on the models that have SFP+ 10G uplinks, not on the ones that have SFP 1G uplinks (I've heard that the 2930F 1G uplinks do seem to operate with the 10G DAC X242 cables, but that was unintentional for now).
NOTE2: 2930F in addition to not being able to support 10G LRM Transceivers (J9152D or older J9152A parts), the 2930F for similar reasons cannot support a 7 meter 10G DAC (J9285D/J9285B). It requires a PHY behind the 10G SFP+ port to support 10G LRM & 7m DACs. You'd have to move up to the 2930M series and use the 4p SFP+ module which has the pre-requisite PHY.
Update to this reply: Our test team seems to have things working fine on the 2930F (with 10G uplinks, JL256A) when using Software version WS.16.05.0004 (you said you were using .0003), using a J9281D 1m or J9283D 3m DAC. If you have a Revision B version of the 1m or 3m DAC, see the "ArubaOS-Switch and ArubaOS-CX Transceiver Guide" for further information.
Please let us know that updating the software solved your issue .