This is the 7423rd most frequent Swedish word.
smångs
"Smångs" is not a standard Swedish word. It may be a misspelling or regional slang.
In this context, 'smångs' is used as an adverb describing the cautious way he drove.
Han körde smångs över bron.
He drove carefully over the bridge.
Here, 'smångs' is used as an adjective to characterize the work as requiring careful attention to detail.
Smångs arbete kräver tid.
Meticulous work requires time.
In this sentence, 'smångs' modifies 'lagt planen', explaining that the planning was done meticulously.