for a while now, I've noticed that I get a great 1st half of the bowl smoke. regardless of baccy or pipe. sweet flavor, smooth and enjoyable. the second half, it usually goes out to signify what is about to happen, relight (quick on the lighter so it doesn't get too hot), the rest of the smoke is smokey, dry and harsh. much like trying to relight when you didn't realize almost nothing is left in the bowl. I figure it is hotter than it should be,but it goes out easily if I don't puff it often enough(same rate as 1st half which is confusing). I started dumping it out when it did this, but am noticing that I have good cake on the top half of the bowl and none on the bottom half of all my most used pipes. I have been at this about 1 year, and smoke about twice per week. most often smoke a black burley from a local shop and a virginia from same shop. some oriental blend and some english from a different local shop. all give the same story. what I am doing wrong?