I had a discussion about this and was genuinely interested but no one could really offer any insight.
In the debate linked to in the question Michael Fallon asserts the following:
Over time, with the carbon price floor and a strengthening emissions trading scheme, the economics of coal generation will deteriorate further compared with gas.
And a bit later on:
I have also considered the argument that the amendment would provide greater certainty to investors looking to build the new gas plant that we all agree will be needed. [...] We already face a significant investment challenge with an estimated 16 GW of new gas plant, and about 45 GW in total of all forms of generating capacity, needed over the decade from 2015 to 2024.
I take it from this that the amendment is intended to increase the generation of electricity from natural gas. If the demand for natural gas increased, this could certainly increase the incentive to invest in fracking in turn.