Ultra long arrows in longbow?

[the rifleman]

Just a quick bit of history---I get my shot dialed in during our summer 3D shoots---my method is gapping at the riser---top of the sideplate is dead on at 15 yards, hold it just a bit higher at 20 and so on until I get to 30 and then put the point on what I want to hit.  This works very good for me at the 3D shoots and sometimes works for me in the deer woods.  I say sometimes because inevitably during the season I will get a shot at a deer and during the heat of the moment I just plaster the broadhead right over the vitals and predictably shoot high.  I've used fixed crawls with good results and this year tuned a very heavy arrow that gives me the 15-20 yard point on that I want.  This has worked well for me.
Thinking I'd like to have the same sight picture for 3D (but knowing that my 578 grain arrow shot out of 42# would not be optimal beyond 20 yards) I have gravitated back to ultra long arrows---32+ inches that leave 6-7" of overhang at my 26" draw.  With these arrows and a very high anchor I can get point ons similar to the heavy arrow so I would be practicing like I hunt in essence with the same sight picture. I have, however found them pretty unforgiving when bareshafting and believe that with my longbows the issue may be the timing of the arrows flex.  The arrow flexes at the midpoint which is farther forward of the riser with these longer arrows and then when the arrow flexes back the other way the back end of the arrow may not clear the riser as my shorter tuned arrows do.  This is just a theory---I have no high speed video to show it, but am wondering if anyone has had experience with this.
When fletched with fieldpoints these arrows fly just fine out to 30 (our max 3D) distance so maybe I don't need to worry about bareshafting or tuning them since they won't be shot with broadheads?
My other option would be to just keep using my well tuned shorter 28" arrows and gap off the riser, which works well for me at 3D.  Then just prior to hunting season begin practicing with the heavy arrows and point on aiming.
Just looking for ideas here.