I'll take both comments - I'd point out that the post doesn't make the 'slippery slope' argument,
Well I, and perhaps JP too, would disagree. The post read to me very clearly as alluding to the slippery slope argument.
... as it's not about whether the bill should be passed, but rather that the comment that the requiremen could just be dropped plays into the idea that when those proposing it say they have built in the safeguards based on the need for this to be the strongest safeguards and that being why the bill.should be passed that they are lying in order to get it through.
Given that some support was according to speeches in the debate, and comments after, from those who thought there should be more safeguards, dropping one would seem to me to make it less likely to pass as it jeopardises some of the support. That could be in theory offset by support from anyone who had voted against it because there were too many safeguards but I am not aware that that was anyone's position.
It is nothing like as simple as you imply.
Firstly there are MPs who think that the levels of safeguards go over the top and the overlay of a requirement in all cases for high court judicial approval is unnecessary, not consistent with other critical end of life decisions and problematic as it would act to delay the process. So those people may be more likely to vote in favour.
But there has been another criticism - specifically that the system isn't equipped to cope with the extra workload, and that has been levelled at both the NHS and the courts. So removing an automatic layer of court oversight, again, make make some MPs more likely to support as assisted dying would have less impact on an already stretched judicial system.
And the final point is that removing automatic oversight of the courts would require an amendment of its own, which would require a vote. So presumably only those who would be comfortable with the amended Bill would vote for the amendment and would presumable be OK with the amended bill being passed. So there is a kind of self levelling approach here - should the amendment pass, then we can presume there is majority support for the amended bill. If there isn't majority support for the amended bill then presumably the amendment won't pass. The only spanner in the works would be MPs playing silly 'wrecking' games - in other words those who oppose voting in favour of amendments that make the bill less likely to be supported.
But, of course, none of this has any relevance to your claimed slippery slope as whatever amendments are passes and whatever amended bill gets passed (should it pass) will be what was intended and accepted by parliament.