I just did a quick Ping test with and without Row 3 and I measured 2.5ms more when using Row 3 or 4.
I guess it’s the second CPU coming in to play.
It is what it is.
I’m thinking of using row 1 and row 2 only to limit latency to a minimum.
As of now I can use the splitter to go to Row 2, all good so far.
But that damn splitter is wasting a block space just for that purpose.
If I could make Row 1 output to Row 2, what a wonderful world this would be…
Proper serial routing 1->2->3->4 would be great.
100% agree, in one of my use cases I reserve rows 3 and 4 for another guitar and I have to use a splitter to redirect the signal flow from row 1 to row 2, and then disable the output from row 1 - terrible workaround but hope it makes sense 
The splitter between rows 1 and 2 and the splitter from rows 3 to 4 cause you to lose a block at the end of row 1 and row 3. Two blocks total signal flow used.
Can’t see a logical reason for not allowing the jumper to go from the END of rows 1 and 3 or to just have an output selection for rows 1 and 3 to go to the next row. Super Serial Preset!
I don’t mind just using the split/mix. Yes, it makes one of the 16 blocks unavailable and it’s a little less intuitive than just routing 1 > 2, but I can’t think of practical application of a signal chain that would need 15 blocks routed serially in a row.
Regardless, I agree; it should be able to be routed 1 > 2 > 3 >4; if nothing more, than for the sake of being intuitive. When I first got it last week, I was confused that that option wasn’t there.