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LTM4653 - EXTVCC for 3.3V output?

I'm using the LTM4653 for 28V in, 3.3V out.

According to the datasheet, for Vout >= 4V, EXTVCC should be powered from Vout (through a resistor R_EXTVCC).  Is there any reason EXTVCC can't be tied directly to Vout when Vout = 3.3V?  Since EXTVCC must be above 3.2V and I_EXTVCC ~= 20mA, R_EXTVCC would need to be well under 5ohm. 

According to the datasheet:

"The primary purpose of this resistor is to prevent EXTVCC overstress under a fault condition. For example, when an inductive short-circuit is applied to the module’s output, VOUT may be briefly dragged below PGND—forward biasing the PGND-to-EXTVCC body diode". 

However, the same would be true of any integrated circuit powered by the 3.3V rail, so unless EXTVCC is more sensitive than the average IC, I can't see why running it directly off VOUT would be a problem.