Can we get a comment from @MICROSOFT please? This issue is all over the internet.
The problem is related to the way the trackpad device reacts to battery performance/efficiency settings.
Microsoft claims this device is best-in-class... this is a great opportunity to prove it.
I'm now suspecting that these issues are related to the Meltdown and Spectre mitigations. Mine seems to be better after I turned them off, and looking back it does seem like they started after the patch and firmware update. So, I'm hopeful that once Microsoft gets a handle on resolving Meltdown and Spectre without killing the machine's performance, we'll be in better shape.
But it would sure help if Microsoft would let us know what's up. If it's NOT Meltdown/Spectre causing this, then it's absolutely unacceptable performance from a $3000+ notebook.
Definitely not related to the Meltdown/Spectre mitigations...
I got my SB2 15" on 11/16 and this issue was there day 1. Others online have also seen this well before the shinanigans recently.