Very very true -- it is indeed block to block, in many parts of the city (not in ALL parts -- you can walk for blocks and blocks in, say, Roland Park or Mt. Washington, and safety/architecture/stability will not vary at all). This is true especially in Reservoir Hill, which many do not even consider a true, unified "neighborhood" -- it is really more a COLLECTION of smaller neighborhoods. There are several historic districts within Reservoir Hill -- Upper Eutaw/Madison, Historic Mt. Royal are prominant ones -- and you will find much higher rates of homeownership in those districts, and also less blight (which stands to reason). This is where I live, in the Eutaw/Madison historic district, up near Druid Hill Park.
Now, Lakeview Avenue has always (or at least, for a long time) been among the more blighted part of Res Hill. Many, many boarded up homes. Probably little to no homeownership on this street. On the plus side, I'm pretty certain the homes are a lot cheaper there, so it would cost much less per square foot to restore one of the houses there, as opposed to on Eutaw, for instance. The houses there are plainer though, and do not have the grandeur that Reservoir Hill is known for (I think it's mostly those 2 story porch front houses on Lakeview). I don't know if you're thinking of investing or living in Reservoir Hill (I saw your other post), but either way, the best way to get a "feel" for the quality of life somewhere is to go there, often, at different times of day and night. My wife and I did that before we bought on Eutaw -- we found that despite the fact that we had to drive past some boarded homes to get to our block, the block our house was on tended to be very quiet at all times we visited, and we liked that. The blocks of Reservoir Hill that have the best potential of becoming "like Bolton Hill" are, in my opinion, the ones on the western and eastern edges of the neighborhood -- it is the inner core that has the farthest to go in terms of overcoming neglect, and fighting crime and trash too, probably. Lakeview IS in the middle, but one thing it has going for it that other parts of the core do not is that it is up north, near the water. If Reservoir Hill as a whole continues to improve and revitalize, all parts near the water are going to go up too, I believe. If you've got any other questions, let me know.