I think one of the things which is hurting this tape is a significant variation in tape speed across its length. (I'm starting to look into tracking tape speed much more accurately across the whole length of the input, rather than optimistically assuming it's a constant.)

Code: Select all

```
leader; start 487892 smps, end 713865 smps, len 225973 smps, speed 0.987
data; start 713866 smps, end 826588 smps, len 112722 smps, speed 0.986
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```