Time for a no risk £30bn stimulus package?

I haven't been heavily engaged in arguments about whether the government should currently be borrowing more to try to stimulate the economy. My simplistic take on the argument is that some people think 'the cost of borrowing is low so we should borrow and invest' while others think that 'borrowing more will raise the cost of borrowing'. Distinguishing between these two arguments requires taking a stance on sentiments in the bond markets - a subject on which there appears to be plenty of strong opinion, but precious little evidence.