I found another way to add the programmer - and it allows me to modify the USBTiny programmer parameters (for integration with VSCode) AND set the extra params -B3! This avoids the need for exposing the Blinks Programmer in VSCode.
The Arduino app uses the programmers.txt file in your Arduino “Application Data” directory for your platform. On my iMac, it’s in //Library/Arduino15/packages/arduino/hardware/avr/1.6.21. (Your version numbers may be different)
Edit that file and add the 5 lines for Blinks Programmer to the end. Save and restart the Arduino IDE.
If you’re using VSCode, you can (in addition to or instead of above) add the -B3 to the extra_params of the USBTiny configuration. And, this avoids needing my backdoor method of adding the Blinks Programmer directly to VSCode.
BTW, you can tell if your modification to USBTiny worked by looking for the “Setting bit clk period” line in the verbose output for the Arduino IDE. For the USBTiny extra_params value of -B3, you’d see below. If extra_params was empty you wouldn’t see the line at all.
Using Port : usb Using Programmer : usbtiny Setting bit clk period : 3.0
avrdude: usbdev_open(): Found USBtinyISP, bus:device: 253:008