	0	pb : 1
	0	wl : 0
	0	wlx : 0
precharge 
	0	_pchg : 0
	10	_bl : 1	[by _pchg:=0]
	20	blst : 0	[by _bl:=1]
	20	_pchg : 1
experimenting... 
time: 20
WARNING: weak-interference `_bl'
>> cause: `wlx' (val: 1)
	20	wlx : 1
event queue:
	30	_bl : X	[from wlx:=1]	(weak)

expect _bl -> X queued 
time: 24
setting another pull-down rule on to overtake X 
	24	wl : 1
event queue:
	30	_bl : 0	[from wl:=1]	(weak)
Fanins of node `_bl':
(from [top-level]):
[after 10]	~_pchg:1 -> _bl+:1
[after 20, weak]	~blst:0 -> _bl+:1
[after 20, weak]	wl:1 & pb:1<1><1> -> _bl-:1
[after 20, weak]	wlx:1 & pbx:X<X><1> -> _bl-:1
time: 28
_bl : 1	[by _pchg:=1]
blst : 0	[by _bl:=1]
step: expect pull-down to overtake previous pull down 
	30	_bl : 0	[by wl:=1]
event queue:
	40	blst : 1	[from _bl:=0]
Fanins of node `_bl':
(from [top-level]):
[after 10]	~_pchg:1 -> _bl+:0
[after 20, weak]	~blst:0 -> _bl+:0
[after 20, weak]	wl:1 & pb:1<1><1> -> _bl-:0
[after 20, weak]	wlx:1 & pbx:X<X><1> -> _bl-:0
time: 30
step 
	40	blst : 1	[by _bl:=0]
time: 40
