Ahh the pine myth, we deal with that a few times a year, so here it goes...… Many people that burn regular hardwoods don't burn correctly, they either have an older stove that they "damp" down to a smoldering mess for longer burn times or they are burning relatively under-seasoned wood.
As with most myths, many novices or under educated wood burners primarily in the hardwood zones of the country will have a mixture of wood, stuff they harvest in the summer, split in the fall and burn in the winter, they will separate the pine (possibly used as kindling or last resort firewood) The pine ends up sitting on a rack for a full season, then bam.. we have a long bad winter, the normal 4 cords of wood is wiped out by march, but its still cold.. the light bulb goes off on the pine that's been sitting on the back rack for a year, they grab the pine and load it in the stove. Now the wood burner is burning truly seasoned "dry wood" in a stove that has been burning damp hardwioods all winter, the chimney is dirty with crud, the operator doesn't adjust the air because they're not use to doing that, the pine lights off, burning quick and hot, lighting off the creosote that built up in the chimney. The pine load didn't do anything wrong, the operator of the stove did many things wrong, like burning under seasoned wood (wood above 20% moisture) not keeping a clean chimney, not monitoring or adjusting the air after a few minutes of loading the stove.
Moral of the pine / soft wood myth... burn only dry wood <20% moisture content, check your chimney after every 2 cords of wood, clean it as necessary, monitor your fire / stove top temps, if you do those things, you can burn all the wood you want.
This isn't made to scare you, but if you need me down by your house with my truck and trailer to take away that pine you have, I'll be glad to do so.