User blog comment:Czyiel/Xander, The Chained Commander/@comment-4296199-20130729151250/@comment-5331854-20130729163528

Attacking a marked enemy after hitting with the Q actually does provide some regen. The W and E would help in getting the hit, but anyhow there's no desireable net gain with the current cost of 50 energy with every skill on every level (which is boring, too).

The cap on the innate is huge, but gaining the upper hand with kills can and will provide a sudden increase. Also, don't forget it has actually 2 caps. One at 50 (with AS, which is a desirable stat for Markmen) and one at 100 (with AD, a very nice addition to the gained AS). The right support will promote this hypercarry to an ubercarry, as he needs no gold for this boost, so he can still buy stuff. It doesn't matter if Xander loses half of his stacks upon death, he still is statistically ahead of his enemies in an even match in two of three offensive stats that are good on any ADC (the only thing missing is crit, which can be bought).

Other than that, I agree with you (as hinted in my wall of text).