There are several docs who do FUE well that do not require the donor to be shaven. Having a smaller procedure like 600 grafts is perfect for non-shaven FUE.
If adequate laxity is an issue, don"t do strip, period. You do not want to risk having a wider noticable strip scar after everything you have been through. You clearly are more of a FUE candidate IMHO, yet I respect your decisions.
In addition, to answer your question about the size of a strip if you were to have strip again, is not as clear as you may want it to be. Why do I say that? Because it depends where the surgeon would be excising your next strip specimen. Again, if laxity is an issue with you, then you certainly do not want the next strip to be excised from the same area as the last four were right? I am assuming that your prior strips were taken from the same area within the occipital zone.
In addition if you did another strip, the specimen cannot be very wide with tighter laxity, certainly not anything over 1 cm wide. And the other missing part of the equation is what is the density in your occipital zone after four prior strips? Is it consistent especially near the prior stip scar? Do you have multiple strip scars there or did they continually take out the previous scar so you are left with one linear strip scar at the present time? If they keep taking out the previous strip scar then the density within that next specimen may not harvest as many grafts as initially thought.
The implication then is that they would have to take a longer strip so that the width can be maintained as lean as possible to prevent it from healing too wide. You may need to be closed with staples or a double closing technique to help ensure a thinner scar outcome when healed.
Also, some very talented docs can potentially take the strip a tad bit wider where there is more laxity noted and thinner where it is tighter within the occipital zone where most strips are excised. This however requires a high level of skill.
If the density within the proposed area of excision varies alot, it may be more difficult to calculate the available/harvestable FUs per cm2 within that next strip specimen. In a virgin scalp, that density is more uniform to calculate. The point is the doctor will need to determine the length of the strip based on how many FUs he can excised from say a proposed 1 cm wide specimen.
In other words, if the density is at say at 60 FU cm2, then he would need to take no less than a 10 cm long strip at 1 cm wide to harvest 600 FUs or 600 grafts. The surgeon would probably take it a tad bit longer, maybe 12 cm long to get a few extras in the event of a few transected grafts from dissecting the strip specimen. Keep in mind I am using an arbitrary number for your present donor density level where prior strips were already taken. I used 60 FUs per cm2 to keep the example simple to follow. If the available FUs are at a higher density level, that's good for you, meaning a smaller strip specimen. Remember, 600 grafts is not the same as 600 hairs. 600 grafts will produce more than 600 individual visible hair shafts.
Some surgeons might suggest taking the strip from a totally new harvest area where the density is more uniform and where there may be more laxity to make the strip wider and not as long. Some may want to explore taking the next strip from just above the ear or parietal zones but I would discourage you from doing that. The scar could be more visible one day as you age.
FUE is sounding better and better all of the time is it not? I am also being careful as to not direct you to either strip or FUE but considering you already had four prior strips taken, I'll let you decide what is best for you. In addition, you never had FUE before right?
The cost difference in comparing 600 grafts between FUE and strip is roughly $2400 US. You may also want to consider those docs proficient at both strip and FUE to get the most broader of opinions.
Anyways, I hope this has been helpful to answer your question my good friend and I always wish the best for you Victim. I know you have been through alot.