Simplify README wording

README.md

@@ -1,6 +1,6 @@
 # dau utils
 
-Host-side operational utilities for DAU bench work
+Host utilities for FPGA bench machines
 
 [![Build Status](https://github.com/dau-dev/dau-utils/actions/workflows/build.yaml/badge.svg?branch=main&event=push)](https://github.com/dau-dev/dau-utils/actions/workflows/build.yaml)
 [![codecov](https://codecov.io/gh/dau-dev/dau-utils/branch/main/graph/badge.svg)](https://codecov.io/gh/dau-dev/dau-utils)
@@ -9,48 +9,49 @@ Host-side operational utilities for DAU bench work
 
 ## Overview
 
-Small, package-neutral utilities for operating FPGA bench hosts. Each owns
-one mechanism; policy (which devices, when to arm) belongs to the caller —
-higher layers such as `dau-build` compose these into their hardware
-command plans.
+Two small command-line tools for the Linux machine an FPGA card is plugged
+into. Each one does a single thing and leaves the decisions (which devices,
+when to arm) to the caller. Higher layers such as `dau-build` run them
+from their hardware command plans; you can also run them by hand.
 
-## Deadman: survive a wedged PCIe device
+## Deadman: recover from a hung PCIe device
 
-A driver/PCIe hang can leave the kernel and systemd alive — the hardware
-watchdog keeps getting petted, yet a clean `systemctl reboot` blocks on
-the stuck device, and the box needs a walk to the power switch. The
-deadman arms a forced reboot *before* the risky operation and cancels it
-on success:
+A driver or PCIe hang can leave the kernel and systemd running while the
+device itself is stuck. The hardware watchdog keeps getting fed, but a
+`systemctl reboot` blocks on the hung device, and someone has to walk over
+and pull the power. The deadman schedules a forced reboot before you do the
+risky thing, and you cancel it once the operation comes back cleanly:
 
 ```bash
-dau-utils-deadman arm --timeout 300     # transient systemd timer; survives SSH loss
+dau-utils-deadman arm --timeout 300     # transient systemd timer; outlasts a lost SSH session
 # ... rescan / flash / probe ...
-dau-utils-deadman disarm                # clean return: cancel the reset
+dau-utils-deadman disarm                # operation returned: cancel the reboot
 dau-utils-deadman status
 ```
 
-If the host wedges before `disarm`, the timer fires `sysrq-b`
-(`emergency_restart()`), which resets past the wedged driver without
-touching it. The same operations are available as a Python API
-(`dau_utils.deadman.arm/disarm/is_armed` and an `armed()` context
-manager); failures raise `DeadmanError` — treat the host as unsafe.
+If the host hangs before `disarm`, the timer fires `sysrq-b`
+(`emergency_restart()`), which resets the machine without going through the
+stuck driver. The same operations are available from Python:
+`dau_utils.deadman.arm`, `disarm`, `is_armed`, and an `armed()` context
+manager. Failures raise `DeadmanError`; if you see one, assume the host is
+not protected.
 
-Arm it before every PCIe rescan, flash, or register probe against a device
-that has previously wedged. Synthesis and other non-PCIe work does not
-need it.
+Arm it before every PCIe rescan, flash or register probe against a device
+that has hung before. Synthesis and other work that does not touch PCIe does
+not need it.
 
 ## Runtime PM: hold and release PCIe power management
 
-`dau-utils-pci-runtime-pm` holds or releases Linux PCI runtime PM for
-devices matched from `lspci -Dnn`. The caller decides which patterns
-matter; this utility owns the sysfs writes:
+`dau-utils-pci-runtime-pm` holds or releases Linux PCI runtime power
+management for devices matched against `lspci -Dnn`. You choose the patterns;
+the tool does the sysfs writes:
 
 ```bash
 dau-utils-pci-runtime-pm hold    --pattern Thunderbolt --pattern 10ee:7011
 dau-utils-pci-runtime-pm release --pattern Thunderbolt --pattern 10ee:7011
 ```
 
-Use `--dry-run` to print the planned writes without touching sysfs.
+`--dry-run` prints the writes it would make without touching sysfs.
 
 ## Development