PIC16F88 USART TXIF NOT READY IMMEDIATELY AFTER WRITING TXREG

I have a routine to send 3 bytes out the uart.  The txif flag is checked 
first to ensure the tx buffer is ready to accept another char. If I put 
a char in the txreg and immediately check txif, it seems to say "ready 
for next char" but in fact, ignores it.

  In the code below, if the nop's are removed, only the first and third 
char are sent; the second does not appear.  With the nops, all three 
chars are sent.

Am I doing something real dumb, misunderstand the uart or ???  Why do 
the nops seem to be needed here?

send3bytes	; typically aa/55/00 or aa/55/01
		btfss	pir1,txif	; uart ready to transmit?
		goto	send3bytes	; uart busy; keep trying
		movfw	databuf
		movwf	txreg
		nop	; may not need 2 nops but fails to send 3 bytes
		nop	; if no nops are here

send3a		btfss	pir1,txif	; uart ready to transmit?
		goto	send3a		; uart busy; keep trying
		movfw	databuf+1
		movwf	txreg
		nop	; may not need 2 nops but fails to send 3 bytes
		nop	; if no nops are here

send3b		btfss	pir1,txif	; uart ready to transmit?
		goto	send3b		; uart busy; keep trying
		movfw	databuf+2
		movwf	txreg

		return

Other possibly pertinent info: internal 4MHz osc, baud rate = 19.2K, 
transmit only, receive not used or connected.
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