I think most pilots understand all the above re satcom and fault finding etc..but from a "drivers" POV regardless of what the engineers need/want there is still the issue of whether a "fresh" align is need for every turn, which takes us back to what the OP's company SOPs/FCOM say on the matter.
For the sake of any engineers contributing whilst I can't speak for our company's 787 procedures FWIW on 744 and 777 at least to ensure a best case align/best nav accuracy we have a requirement in our SOPs to re-align the IRS on every preflight, and a requirement to ensure we, i.e the flight crew, enter the present position prior to that align. That means turn the IRS(s) off and then back on again, even if the ground engineer says he/she has just done the necessary just before we got on board...it does sometimes raise comments or an eyebrow..it's nothing personal, it's not a case of not trusting the ground engineers, but in the case of some bizarre nav problem post launch I think most of us would be like to be able to say we'd stuck with the company procedures..
Last edited by wiggy; 30th Dec 2017 at 08:54.