I have uploaded some more pics of my lap joints - look at them, study them...and do it differently!
My joins are a bit "scoopy", as I removed too much material too soon along the lap section of the arc of the hoop; you'll want to cut in very gradually along the arc so that the entire join section retains the thickness of the hoop. You'll see in the pics that the hoop at the join[s] is not bulging out on the outside, but rather "scooping in" along the inside.
Well my middle name is "good enough" so overall I'm happy with the cut-downs, but I do have some sections of the "donor hoop" left over so I might carve out some thin pieces to lay in over the joins, to achieve consistent thickness all around.
About the patch issue and the feasibility of doing this with one join - it may be wise to cut the hoop initially at two points, and use the cut-out section for the patch, instead of making one cut and removing most of the overlap. OTOH my issue with the one-join approach might have been due to the flexibility of the cymbal case I used as a form. If you use a solid wood form with no "give" to it, the one join approach might work. Wish I had more hoops to investigate this with...
Randy I would suggest using a very strong outer form for your job - the sprung tension is quite strong, hard to wrestle the hoop into shape, so having a strong form to lay the hoop into is a big help. With smaller hoops, sprung tension may be even greater than with 25" to 22". Using the drum shell as an inner form might lead to problems and put too much stress on the shell.
On my kit, the lighter-hued maple hoops really helped to make the bass drum look bigger, visually matching it better to the somewhat big-looking Gretsch 9X13" tom.
Mitch