Ah the ambiguity of woodworking terms.
The text describing the tool in question, the Plane Screwdriver, says
"We designed this screwdriver to make it both safe and easy to remove,
replace or adjust the cap irons."
There are two removable parts held with screws on my bench
planes - more specifically the metal ones (I've got s few Steve
Knight early woodies too). One holds the chip breaker ( called
that because that's what it's designed to do) and the other holds
the lever cap. Now, having looked a the photo next to this tool's
picture I see that it's intended for the screw for what I call
the chip breaker. Now, having used this tool on THAT screw,
I find it works really well. So now I suppose I should wait and look
for an upcoming special screwdriver for the "lever cap screw"?
Is what is known as the chip breaker here called a cap iron
acrossed the pond? Bad enough with rabbet/rebate, joiner/
jointer, board/timber, planer/thicknesser - and the pronunciation
of the word schedule (sked-yule vs shhhhed-you-el)