It's certainly not "problematic" in any real sense, but it's certainly far from ideal.
Regarding seating closer to the lands, there are many benefits and few downsides. When working up a load I generally start with a jump of .040”. After finding an accurate node I'll then seat both closer (.010" jump) and further (.070" jump) and see if either produces a tighter group.
I'm well aware that concentric ammo reduces group size, but I'm of the assumption that ALL reloaded ammo intended for precision work (for paper targets, for hunting, etc.) has as little runout as possible. The 21st Century Reloading concentricity gauge is the best tool I've used for indicating runout. It's not cheap, but if mine disappeared tonight I'd have one ordered in the morning.
Loading close to the lands offers more benefits than just precision. In my experience, SD typically decreases and velocities typically increase given equivalent powder charges. In addition, seating a bullet further out in a case allows for more powder or prevents a load from being compacted. As long as you stay within pressure limits and within an accuracy node, these are good things.
The way I see it, it's not so much about the problems caused by jumping a great amount (say anything over .090") so much as it is what's given up by not being able to get a bullet close.
And again, this is all subjective. What matters to me likely won't mean a hill of beans to someone else.