strategy `weighted-lines` not working properly

Steps to reproduce:
`wwt --strategy weighted-lines line blockchain.go 224`
(file: [github.com/go-ethereum/core/blockchain.go](https://github.com/ethereum/go-ethereum/blob/master/core/blockchain.go))

```
[184-298] NewBlockChain :: function_declaration
  3	 - Martin Holst Swende (martin@swende.se)
  1	 - Péter Szilágyi (peterke@gmail.com)
  1	 - gary rong (garyrong0905@gmail.com)
```