The problem with any proper resignalling of the line is that several of the stations duplicate the situation at Poppleton. So at Starbeck and Cattal you have a signal right next to the level crossing and at Knaresborough the signal is next to a wicket gate crossing. At Hammerton on the Harrogate platform there is no signal protecting the level crossing. As far as I know the current signalling regulations stipulate that a newly installed signal protecting a level crossing should be a minimum of 200 feet from the crossing , as was the case with the ill fated colour light at Poppleton. So if they wanted to resignal Cattal the new signal on the Harrogate platform would need to be 200 feet from the crossing and thus the platform would need to be extended OR they would need to build a bridge to replace the crossing. Whilst that would be feasible (at huge expense) at Cattal and Hammerton it would be virtually impossible at Starbeck and Poppleton. Whichever way you slice it, resignalling the whole line and/or doubling it is going to cost a lot of money.