Yes, the guide is only for ripping small pieces off the edge. If you want to rip further into the board you can remove the guide and clamp a long guide to the wood then run the base plate of the saw along the edge of the guide rail. You have to calculate the offset from the edge of the base plate and take that into account when you clamp the guide in place. If you don't need to worry about the cut piece you can screw a guide to it where clamping is a pain.
When you start to get more fussy you realise it's difficult to get a straight guide or one long enough that stays put etc. so the track saw becomes more desirable.
Yes, the guide is only for ripping small pieces off the edge. If you want to rip further into the board you can remove the guide and clamp a long guide to the wood then run the base plate of the saw along the edge of the guide rail. You have to calculate the offset from the edge of the base plate and take that into account when you clamp the guide in place. If you don't need to worry about the cut piece you can screw a guide to it where clamping is a pain.
When you start to get more fussy you realise it's difficult to get a straight guide or one long enough that stays put etc. so the track saw becomes more desirable.